this is the link to the unit I was referring to. It's not working, the indicators on it are not coming on . By the way I wanted to thank you again: because of you video I was able to properly test both fans and fortunately they're working.
For clarification I am talking about the same plug on the fan that you have the wires in in the video. It is similar plug on the 2006 TDI Jetta but it has 4 tabs two large and two small with the wire colours as I described. I can take a photo of it today and send it to you. the plug has these cables leading to the large fan. Red large, Brn Large, Black small, Grn Small.
I got both fans on and turning the right way. Outside temp +25°C today above the 18° on the dial. I had to turn the Blower to 4 and turn off eco mode. Before all this I went through all the VAG settings and it told me that no Output test was available for this car TDI 2006 BRM Jetta. So there was no luck there. Then I tried the blower at 4 and re-leaved to see them turn on. Thanks for your help.
mronemanband1 Yeah, sorry... thanks for the info. This is one of my old videos where I did not go into detail. There are video pop-up annotations, but they only show up if the viewer has his/her annotations enabled. My newer videos have better lighting & text overlay... even some talking now and then. Thanks for watching and taking the time to comment!
I just attempted to turn on annotations. On my cell, option doesn't appear. On my PC, it was already enabled. So ... I never saw any annotations especially at the moment of testing into the connectors ... I'm curious where is the annotations normally displayed? I tried full screen and comment screen visible modes and never saw an annotation either way. ARE there any annotations for this video? THANKS!
@@christophermaxwell9621 Year, make, model, engine? Follow this video to quickly check fan operation. Let me know your results: th-cam.com/video/Roh6RCs8IJk/w-d-xo.html
Thanks for this video!! Exactly what I needed to find. I will check the fan operation tonight. Noticed that fans weren't operating at all 'cause my AC was intermittently blowing warm/cold air. Went through this 3 years ago. Replaced both fans and the FCM. Hopefully fans are ok. At least this time they spin freely, unlike last time. Thanks again! Oh, and the "let there be light" video, was HILARIOUS!!
I was gonna reply to the light comment, but then you posted this... also check the fuses on top of the battery (the green fuses). Thanks for watching & taking the time to comment!
EXO While I have your ear. I have to say I think your videos are fantastic. In depth and really helpful. Fantastic Job. I will send you an email with the image of the plug.
hi thx for the video, I have a chev Caprice ..the engine fan does not work on high speed when the engine is running but when you connect it directly to the battery it works on high speed, we checked the fan relay both are ok, ... sometimes the car is overheating when in heavy traffic, the electrician suggested to connect both relay and to work on high speed only
Finally got time to mess with my car both low speeds were gone tested fan motors individually and only 1 fan had a high speed after I got it out but both were woking in car lol def bad fans. Replaced fan assembly fans working right again and it is possible to replace fan assembly without taking radiator out on an mk4 gti. its tough but doable i took the small fan out and put it back on shroud after i got it into position and mounted. The aftermarket fan assembly was larger than oem.
I used the 3 pin thermal switch connector to check mine. I believe the red wire is hot at all times. Jumping this wire to the other 2 pins will turn on both fans (one pin for high speed the other for low speed). High speed only works with the ignition on
Yes, good tip.... I like to check at the fan connector though, that way you know 100% that the issue is at the fan (if a speed does not work). You could have a break in the wiring between the fan switch & the fans or the fan module (for high speed).
@EXOVCDS thanks for getting back with me. 2001 golf GL 1.9 diesel tdi. I bypassed coolant fan switch and they both come on .and when I have car started and do the same fans come on.
I just tested my fans speed. To test Low speed test was good. I tried high speed but failed. I wanted to know if I could test high speed with middle ground and Red/White positive. I did your method as well (outer terminals) no power to high speed. Thank you for your great videos and your time.
Brown is ground... needs to be negative for both speeds. If you only have low speed and nothing happens when you attach the positive to the high speed wire, then high speed is burnt out.
In responce to your Email. The Second smaller fan would not run when the AC was switched on. So I took out the fan and bench tested it. Smaller fan would not work and larger fan only works on high. a friend of mine at the dealer said that if one fan wasn't working it defaults to high on the main fan (maybe low isn't burned out.) So I changed the small fan. I am currently looking into how to do the VAG test. I will let you know how it goes. VAG gives me no error Code for the broken Fan.
First off The terminal has Red large, Brn Large, Black small, Grn Small. When I hook - black to Red on the plug they turn on reverse high (obviously +Red battery should go to Red on the fan) which is why reverse fan. But when I put -black on BRN and +red on Red I get nothing. Doesn't turn at all. Fan only turns when I reverse my leeds. Not sure why. I have to watch this in slow motion to see what you hook up to what lol.
I have this same problem. Pulled out the fan and replaced the small one. Now I can get both running on high but not low. What is the right terminal hook up to get low. Power to both large runs high. Power from large to any small and no fan. (Also side note black attached to lead shown my fans also run reverse arrow. Reversing the leads won't run at all. Which is a bit odd.) What is the right terminal to get low running. Could mean my large fan has burned out low. Thanks great vid.
Thanks for the quick response! The Hanes Manual did the same thing. Told you run the jumpers to test the fan but did not indicate which one is which and of course the wiring diagram did not show it either. Keep the videos coming, I am allways working on my Jetta.
The one shown here is a 3 leed fan I have the 2006 TDI has 4 leeds in the plug. This shows 3 leeds looks like this but they changed this after this model. My old rabbit from the 80's and Golf from the 90's were like this too 3 leeds.
Thanks for puttng out all these great videos, saved me some time and money! Have a question..98 Beetle 2.0L, a/c does not blow cold air, replaced the fuse box on top of the battery(had the common burned fuse issue), a/c clutch does not engage, checked radiator fans low/high with jumper wires from thermo-switch(both worked), but fans do not run if I turn the car to ON and press the a/c button....do you have suggestions on next tests? Maybe an issue with fan control module?
Gene Thoman The A/C system needs to be pressure tested... if low on a/c charge, the system will not activate. A problem with the ambient temp sensor can also cause no a/c. A shop will not charge much to pressure test / recharge the system.
took it for a drive with new control module. radiator is red hot! still no fan. touched the hex of the fan switch and that was very hot! I may just have been unlucky and got a dud?
hi im get crazy with vw cnddy 1.9tdi... with key on fan run i replace sonsor ,,same problem,, i test swtich for coolant 2 pin with key on 5 v .i put led to battery + another led to coolant - come up 12 v its mean both is good ,,after that i test fan swtich 4 pin low speed high speed there is to power and 2 grown ,,,one of my grown wire is 9 v
is the sensor on the radiator the only switch for the engine being hot? also I disconnected my coolant temp sensor and it still picked temperature up on the gauge. I wanted to see as the wiring diagram I found had one wire from the ecm to the engine coolant blower motor relay. k12 on the wiring diagram. I can't find this on the car it's separate from the control module.
I have a 2004 VW Jetta 2.0 GL where both fan speeds operate fine manually but I have no low fan speed in auto mode. I have tried new coolant temperature sensor, new fan control module and new radiator temperature sensor and the engine temperature dashboard indicator climbs from the center position, (190°F) up pass two tick marks before the fans come ON in high speed mode. The cooling system is able to recover and come back down to the center position w/o triggering the overheating alarm. Why doesn't the low fan speed is activated? Thank you in advance for your time and keep posting more helpful videos.
Disconnect the radiator fan switch (below the battery in the radiator), trigger low speed manually with a metal paper clip across the 2 wires in the radiator switch harness plug. Can you activate low speed like that? If yes, then the switch is faulty. Watch this video about faulty new sensors: th-cam.com/video/mlzDtTSHV6w/w-d-xo.htmlm
I can operate both fans low speed by jumpering radiator connector pins 1 to 2. If I jump terminals 2 to 3 the manual tells me that I should get high speed and I do not, nevertheless they come ON at high speed in auto mode.
Ignition needs to be ON to activate high speed, since the Fan Control Module needs to be "awake". If you replaced the radiator fan switch already... it could be a bad switch. Does the lower radiator hose get hot as well? You might have a thermostat that is not opening fully.
I am going to follow uh our suggestion and place back the original radiator temperature switch and see what changes. Thank you for the helpful video link, keep up the good work.
Jose Sousa Let me know what happens! What was the original issue? Same thing? Running hot? No / little heat inside the car can be because of a bad water pump.
have checked fans small one doesn't work motor is dead. still expect the other to kick in? so I replaced the switch. did a thermo too just in case as it was cheap. both pipes get hot when the car is sat still and not driving as when the car I driven the radiator cools it down? deaccelerating from hard driving brings the temp up to 110 and reached 130 once. but it was sat at 110 I opened the bonnet and no cooling fan
+woody95124 Looking at some of my old videos, I question why I even bothered posting them (low light & no talking). I think my new videos have better lighting and the text overlay (instead of annotation pop-up like in this video) helps a lot. Thanks for watching & taking the time to comment. Oh, not so much smarts... more so common failure items due to age.
+Thomas EXOVCDS .its ok on oldervid..U move pretty quick!..but that's how u roll bud....How do you know which terminal is ground & hot to make fans work/...I 'am some sort of mechanic...not pro...I surely don't want to fry anything...thnx
woody95124 On VW & Audi, brown wires are ground. ALWAYS confirm with a wiring diagram before applying power & ground to be sure!!! The old systems such as this one are easier to troubleshoot.
Great video! Question: Once you've determine that the fans our burned out on low speed what's the next step? The control unit inside the car is not turning on and I did replace the bad fuse box on top of the battery.
didn't work with aircon anyway. Haven't tried taking it for a drive. should the fan kick in off the coolant temp switch and the radiator fan switch. of just fan switch?
+MiniBikerUK Mainly radiator fan switch... but depending on the system, the ECM or the Fan Control Module will turn it on when a temp sensor gets too hot.
i have a beetle turbo s 2003. the fans opperate on low but not high. ive changed the melting fuse block. also changed the large ac and fan controlor module, and all the temperature sensors on the car, even the fan switch in the radiator. do you think my high speed in the fans has burned out? they both run on low when i rumper the conector, but wont run when the high is contacted.
High speed bypasses the low speed resistor... so in theory, if low speed works, so should high. Watch the following video... do the same thing that I did AND record a video (so that I can see how & what you did). Post the video on your channel and then let me know when the video is up or post the link here. Also, use a test light to verify that power is getting to the high speed wires at the fan connectors.
Hey. I have a 2000 jetta with the vr6 2.8. the radiator fans quit and it blew my radiator. neither fan will work. could you write a walkthrough of what i should do first to see why they just quit. i could hear a motor like sound come from in the engine bay. it sounded like it was near the intake in the back. please help!!! thank you.
Thinking my fans are dead in my Audi A4 B6. I have the wires stripped up top to test the fans but don't know where to go from there. Blue and Orange wires come from one fan, then Yellow and Green to the other fan. Which color should I hook up to the positive? Is the correct way?
This video is for a VW A4 as in mk4 (4th generation) Golf or Jetta... your "Audi A4" is different. Your fans are "pulse width modulated" (turned on/off rapidly) by a fan module. Testing is different than in this video.
Also it's not feasible to test them up top, how do I make a jumper cable with a male pin it to test at the plug like in your video? Or can I just insert a twister wire in there? Never done this before.
You are correct, testing can not be done the same way.... you need to check for a "control signal" at the fan module. If Power & Ground are present at the fan module AND a control signal is present, then the fan module is bad.
Well I've already removed my fan control module to try to test my fans individually. I have two cable coming from each fan to the module. Purple and Orange from one and Yellow and Green from the other. What colors would be the power and ground?
Because they are "pulse width modulated" it is easy to burn them out... if they are manually activated for too long (hence the different testing method). If the fans did not do anything, yes, they are probably bad... common with age and especially on vehicles that constantly us the AC.
Hi Thomas. I have a problem on fans at my car audi a6, 2.7tdi,2009, engine CANA. when i switch ignition or star engine after 20 seconds the big fun run at full speed.it run all time and after switch off engine it shutdown after 30 seconds.i check fans manualy and work perfect. i have 2 errors:1. coolant fan control circuit 2:electric malfunction P0481. and 2. fan 1 control circuit: short to plus P0692. i visited more services and everybody say change both fans but i check them and its ok. Please help me with an idea what i can check? i check voltage on jack. i have 4 wires in jack. 2 big (+ and - permanently) and 2 small, 1 from ignition and apear voltage when switch ignithion and other one small which have 12-13v when fan run at high speed. Normaly on that wire i must have 1.2 when its close and 1.7-1.8 when start to run at low speed.(i check this on second fan from AC). Please help me!
The fan is controlled by the ecm... it should get an on / off signal. If there is a wiring problem, then the ecm can not control the fan. If the fan module is faulty, then the ecm can not control the fan. Disconnect the harness plug and look for an on / off signal on one of the wires. If one is present, then the fan / module is bad.
Your videos show good procedures but it would help if you could use more lighting to better view what you are doing. It's so dark that you can't really see much. Would also help if you add more narrative.
I tested my fans using the smaller 3 wire connector I saw another guy use in another vid, and only low works. Supposedly that means the fan relay module works, but if so then what doesn't work? could it be a resistor for high mode? both fans work on low neither work on high.
rpaull3 The Ignition has to be on for high to be triggered via the 3 wire connector (rad fan switch) in the radiator. What are your issues (if any)... overheating? A/C not cold enough? etc.
Thomas EXOVCDS hey i have the same problem, car overheats because fans won't turn on. I've tested the fans on low, they work fine but on high they don't work even with ignition turn on. What's the problem the FCM or the radiator thermo switch?
02 jetta fans work on low speed when ac on. Tested with jumper from the plug at radiator.only got low speed. Fans worked properly until i had the tranny and clutch replaced.
Actually my son's car but I believe it's both....going to try n rest fans tomorrow. I did notice that when I was checking power the motor was like magnetic to test light. Normal ?????.... But there was no issue with fans or cooling until tranny swap. Tested temps with laser rad was just over 100 n block was 200
th-cam.com/video/Roh6RCs8IJk/w-d-xo.html Transmission / clutch removal should not impact fan operation. If you don't have heat inside the vehicle when heater is put to max hot, then the water pump is no good. Temperature gauge should stay in the middle... if it creeps to the right, then the thermostat is stuck or the water pump is not working. If the temperature does NO climb when the radiator fans are triggered manually, then the radiator fan switch is not working as it should (or the thermostat is not opening).
Thomas on my seat 1.9 tdi asv engine 2001 if i start the a/c both of the fans start to work..but how can i tell if they're working on low or high speed?..what speed is normally engaged when you turn the a/c on?.. The low speed or the high speed?..if the low speed on the fan is burnt when i turn on the a/c will it engage directly the high one or will it stay still and not work?..
Andrei Ailoaie As far as I know (understand the wiring diagram) low speed is controlled by the radiator fan switch that is mounted at the side of the radiator. The high speed signal (from the radiator fan switch) goes to the Fan Control Module. The Fan control module turns on (I believe) the high speed (at a reduced speed) when A/C is selected. If the rad fan is fed power directly to the high speed wire, the fan spins faster than when A/C is selected (which leads me to think that the fan control module does some kind of speed reduction). I could be wrong...
low fan speed has burnt out so what does that mean new fans or new resistors? ive just noticed my 40amp strip fuse has blown on my mk4 golf and with air con on my low fan doesnt work.... which means its either the fans or the fan switch relay? any advice is highly appreciated
mathersooh If it's the resistor in the fan then the fan needs to be replaced. Test the fans with jumper wires if it is the same setup as in this video (bad lighting sorry). Each fan should have 3 wires. One brown & 2 red (with tracer colors). Attach the brown to battery negative and attach one of the red wires to battery positive. The fan should run at low or high speed depending on which red wire gets power. If you only have one speed (high or low), then the other speed is burnt out. We replace the fan... I'm not sure if it can be taken apart & repaired (I don't think so).
+MiniBikerUK Everything is labeled... if the fan works when you bridge the sensor & the radiator gets hot, then the sensor is no good. If the radiator & sensor do not get warm / hot, then something is preventing them from getting warm / hot.
hi thomas my wife has a 99 beetle with 2.0 gas AC works fine blows cold air and all but either fans are working i replaced both fans about a year ago they were working fine until now do you think it could have something to do with the fan control module thank you !
I recently replaced my radiator because it was leaking. I didn't take note of which fan harness connecter went to which when I took it out. I just reconnecting them assuming that it looked correct. Does the larger/smaller fan have to connect to a specific one?
I have an 01 A4 1.8 with AWM. The coolant temp gauge shows perfect temp while driving but after turning off and then restarting a few minutes later the temp shows one or two clicks above middle and then comes back down. The radiator fan runs fine but the aux fan only comes on when I run AC. Isn't the aux fan supposed to run based on coolant temp switch and after engine is shut off or is it possible the relays or module are bad? I just replaced timing belt, water pump, and thermostat and this started happening. Heater works fine. Ac always cold. No MIL and no other codes.
+matt audia4 Do you have an electric coolant after run pump? Might not be circulating coolant after shut-down. I'd have to check a wiring diagram to see what all ties together. Little fan should kick in when things get too hot... but is usually not needed, because things usually don't get too hot.
+Thomas EXOVCDS I don't think so. Just the fan on the left that is belt driven and the one on the right that is electric and comes on when the ac is running. I thought it should be also engaging based on coolant temp that the 4 pin switch senses (blue color on lower radiator hose) but I am not sure if that would be faulty or if there is something else I need to troubleshoot. I can't seem to figure out what is causing the temp gauge to show hot after a shutdown and restart.
+matt audia4 Like I said... if there is an electric water pump that is not circulating coolant after the engine is shut off... then engine temperature will rise. I'll have to check a wiring diagram... otherwise,l like I said, that fan should not need to come on unless temperatures climb... and yes, it should be triggered by a temp sensor or fan module (aside from AC switch).
Here is the problem in resistor. 1st speed going via resistor. When resistor blows does not working slow speed. I had this problem on Vw AG car (Seat Ibiza 6L)
Very good info !!!! I have a problem... its a 2000 beetle the a/c not working - the compresor runs but the fans are out !! any hint on this please ?? we try a diferent radiator fan control unit and still the same problem ! one guy says its the fan swith !the triangular shape ?? but I dont know please HEEEELLLLPPPP !! BTW thanks for this tip !! LOL :-/
hi i have an 04 audi a4 1.8t and when i bought it it came with cooling fans in the trunk with no control module and 1 of the fans wouldn't come on at all, so i got new fans and module at a junk yard my question is would there need to be coding to the new module with vag-com or not? thank you
met rusani If it's out of a same vehicle, should be ok... be sure to keep an eye on engine temperature after installing. If it still gets hot and the fans don't come on, shut it off and check everything again.
Hey! Great vid! One question, my fans don't work on low speed (A4 VW Jetta) I installed a new Fan control module but no luck, do I need new fans? Thanks
I have a 04 Jetta TDI 1.9 that was having a slight heating problem so I switch out the radiator fan assembly because I was hitting temps of 235 which is not normal for the car. Both fans for now but I'm still having an issue, my fans turn on when the car is turned off. Any advice? Thanks in advance
Could be electrical or a thermostat issue. The engine "should not" overheat while driving... if it does, it's not a fan issue. Check for correct coolant circulation / water pump operation as well as thermostat operation. Replace items as needed.
Thomas EXOVCDS I wouldn't exactly say overheat but abnormal temperature readings, it would normally stay around 190 or so now it gets up to 230-233 which is weird. But I'll make sure to look into it. Thank you
Hello, I have a 2007 vw Jetta that when I turn on ac the fans don't come on, when the engine gets to 190 degrees both fan will work. If is the fan could I jump the wires so will work when ac and heat is applied till I get the new one? It does get cold after the engine is at 190 degrees or I'm driving.
HAROLD De La Matta The following AC pdf includes Automatic AC and Manual (use whichever diagram applies to your car) fkh161.ca/VW/A5/mk5AC.pdf The rad fan diagram is just for basic rad fan operation... which you know is ok. fkh161.ca/VW/A5/mk5RadFans.pdf If you have Automatic AC, check the system for fault codes... if manual, when pressing AC, the ECM needs to get a signal that AC was activated, so that it can trigger the fan module. I think that with a scan tool, one can look to see if the ECM gets an AC signal. Check all the fuses (powers) & grounds that are indicated in the pdf's.
Hi, I have problem with my fan. when I turn on the a/c after 20 or 30 min. the fuse (40 amp that is located on the top of battery) get burn and both fans are turned off also the compressor. both fans are news and I have changed 3 times the fuse. without a/c the big fan start correctly but I hear it too noisy, I think start in high velocity. I hope you can help me with this problem. thanks.
Hello, I have a 03 1.8t beetle , that the fans only work when the A/C is on.. I checked the low and high speed connector but only the low speed works.. is there something else I have to check or do I have to replace the fan.? Thanks.!
+Thomas EXOVCDS.. yes heater inside blows hot, I replaced the thermostat also and hooked up my scanner since these cars come without a temperature gauge and the temperature gets up to 210 and the fans still won't kick on.
+Thomas EXOVCDS .. The fuse was good, I already tested the fan high and low spd and it works.. so that tells me that the relay and fans are good so I came to the conclusion that I have a bad thermo coolant fan switch.. possibly?I'm going to replace that and see what happens.
+Ernesto Madrigal Yes... sounds logical. Just wanted to be sure the thermostat & fuse are OK. if you have power at the fan switch plug, probably a bad switch.
@@EXOVCDS Thanks! Well, then ... SOMEhow BOTH speeds of BOTH my fans are dead ... AND the sockets TO the fans have a FRACTION of a volt ... But all the fuses i can find are fine! Bi-zarro! So i got two more fans and that control box above the fan sockets at junkyard ... heeere we go! Thanks! (And how weird i cannot find that brown wire stated on any image for the socket on google images!)
@@fm2dmax I don't know how you are testing or here you are testing. Follow this video to check the fans via the radiator fan switch harness plug. th-cam.com/video/Roh6RCs8IJk/w-d-xo.html Post a video so that I can see your test results.
Hi thomas hope you're doing great ! i have a slight problem with my MK4 SDI , when i bypass the thermo switch (the triangular connector) i have only the first speed that works , but when i i try the second speed nothing happens , what should i check ? also note that when i remove the fuse N°16 from the fuse box , the fan doesn't come on at all ..any tips ? thanks a lot , enjoy your day.
@@EXOVCDS thanks for takiing time to answer my question , well after switching the ignition to ON position the second speed kicks in ...but i was wondering why they don't work when i remove the fuse number 16 ?
Any help would be appreciated here is my issue: I have a 2001 audi tt with AWP 180hp AWD my car has two short to ground codes one is CTS short to earth and the other is fuel sending unit short to earth. My gauges in my car for both of them don't work at all and the cluster has been rebuilt. I have replaced the fan control module with no luck, next i have on order the fan temperature sensor, and also new fuse box for battery because my blade fuse going to the fans looks a little bent and the wire looked a little melted the red rubber. is there anyway to ground both of these manually if so can u tell me what wire to look for and how. please help im stranded.
What I would do is use a scan tool... access the instrument cluster computer and then perform "output tests". If the gauges / needles do NOT move, then the problem is with the instrument cluster. If the needles DO move, then you have wiring issues. The CTS has 4 wires, 2 for the ECM and 2 for the dash... use a multimeter to check the wires for continuity / shorts to ground (ECM & ICM disconnected). You'll need a wiring diagram to determine where the wires are on the EMC & ICM connectors.
+MiniBikerUK If you have an infrared thermometer / heat gun. Check how hot the sensor gets. If it does not get warmer than 97c to 110c, look for a radiator restriction. What year is your car... I'm trying to find a wiring diagram.
I have a vr6 mk4. the secondary water pump keeps working even when the car is shut off, and drains the battery charge, do you know if this issue has to do with the coolant fan module? Good video by the way
Temperature sensor or fan module... me thinks. I'd have to check a wiring diagram if there are any other control devices that are part of that circuit.
The wiring diagram I have doesn't show how many fans... how many fans does your car have? 2 electric or one belt driven with 1 electric? According to this diagram, the fan module is controlled by the ECM... if you remove that setup... how are the fans triggered when AC is used? You'll also end up with cooling fan OBDII codes (with a check engine light in the dash). fkh161.ca/Audi/A4/03AudiA4CoolingFan.pdf Why not fix the issue... it's probably cheaper than trying to convert back to an older setup.
I have 2 electric one, so you mean if I install switch, I could be have trouble code? If it’s turned on my engine check sign, than I am not gonna do it, but I want to know what situation my fan is turned on, because it some time on and some time doesn’t
You can see from the diagram that the fan is controlled by the ECM... the ECM keeps an eye on the engine temperature and then sends a signal to the fan module. You could have a bad fan module... check for fault codes. Using a scan tool, run output tests to see if the fans act-up (don't come on). If you have a multimeter, you can do some testing: th-cam.com/video/oqdv4cm86Ns/w-d-xo.html That video might not be the exact same as what you have in your car... you can use the wiring diagram I posted earlier, to check things.
Hey I have an 98 audi a4 1.8t and my engine is over heating cause my fans won't kick in to high speed I have Changed thermostat , coolent temp sensor..and I have checked the fuses any advice?
356gk T Do you get heat inside the car? If the heat disappears after a short while (even when set to max heat)... you either have air in the system or the water pump is broken / not pumping coolant.
***** I'm not getting any heat the car just keeps running until it over heats the second speed won't kick in I replaced the thermostat coolant temp sensor and 40 amp fuse all fuses and relays are fine I have not yet Checked 214 relay (cooling fan ) I read there is a thermo switch though could this be the problem?
i really hope you can help me. I have a 99 vw 1.8t passat. I recently replace the head gasket because it was blown. It ran good for 6 months and blew again because it wasnt properly torque. So I replaced it again. It ran hot 10 days later. I notice that the AUX fan isn't coming on when its running hot. I replace the water pump, Coolant temp sensor and the coolant fan switch just last week. I replace the Aux fan relay also. It still runs hot after 10 mins of driving. I dont want to trash the car cause its my only transportation. I was under the impression that the fan switch controls the aux fan. its new and the fan still isn't coming on. I purge the air out the system the best I know how also. but still running hot. the temp light is coming on even when there is coolant in the expansion tank. Do you have any ideas. By the way the aux fan will come on when the ac is on.
Key on engine off... turn the heater fan on and press the a/c button. Both fans should run... if no, check the fans individually for power. If power is present, replace the fans. if no power is present, check the green fuse on top of the battery. Run the engine and keep an eye on the temperature gauge. monitor the lower radiator hose temperature. if the lower hose does not get warm by the time the needle is just past center... replace the thermostat.
Your "fan control module" is part of the large fan. The ECM tells the fan module how fast to spin. Communication errors between modules, high ac pressure, or wiring issues can cause the fans to be on full speed all the time (fail safe). You need to check things. th-cam.com/video/oqdv4cm86Ns/w-d-xo.html
So my vw jetta 1.8t i just put a new motor in it how do i check if my fans work my temp went to almost 260 shut the motor off but the fans didnt kick on what so ever when it idles it doesnt overheat
Definitely will i appreciate it , also i replaced my rear main seal and im really hopeing i dont have to do it again but noticed oil on the right side on my oil pain when i actually let it warm up by any chance would it seal off or do i have to take my transmission back off and flywheel and all that
Scan for fault codes... loss of communication with the fan module can cause the fan module to turn the fans on at high speed. Could also be a temperature sensor issue or ac pressure sensor. Many things to check.
+Antwain Geffrard Not sure... how warm is the lower rad hose (going to the thermostat)? The viscous fan clutch should get stiff as the engine & radiator get warm... does it? Is the water pump belt tight? I believe this engine uses an external mounted water pump. If all else fails, can you take it to a VW / Audi repair shop for "diagnosis"?
The waterpump belt is very hard ane has cracks in it. I had a new one but haven't put it on yet. I didn't believe the belt would cause problems unless its slipping in the pulley
I did this and the fan (if you're facing the car; no the left works but not on the right. I checked the fuses. But when the car warms up neither fan turns on and causes it to overheat. what would be your next step?
The car should not overheat if only 1 fan is working. If none of the fans come on by themselves, either the radiator fan switch is no good, the fuse is blown or the water pump is not circulating coolant. Do you have coolant flowing back into the coolant reservoir when the engine is running? Watch this: VW A4: Good Water Pump Flow at Idle You can remove the hose and point it into the top of the reservoir while someone revs the engine. If you do not have heat inside the car (even though the engine is warm / hot) that's another sign that the water pump is bad.
Okay, so I rerouted the fan to make one of them work, the other does not work. But I no longer believe the fan is the problem. I just replaced the radiator and bought new one (from autoone). It is still overheating. something I noticed is the bottom hose that connects to the radiator stays cold even when it's overheating..
Do you have heat inside the car? If no, your water pump is no good. If you have heat inside, then your thermostat is stuck closed. What engine is in your car? Have you checked for flow into the reservoir? Was it overheating before the radiator was replaced? Did the radiator blow because it was overheating before?
Okay a little back story, 2 thing's happened around the same time. Serpentine belt broke ( was 100 yrs from my destination so it didn't overheat. The pulley bearings went out and locked up causing the belt to break. I replaced both the pulley and belt. then the radiator was rusted and started to leak. so I replaced it. I got super hot heat. I just rerouted the fan to turn on with key ignition. it seems to be good when it's parked but when I drive it it overheats.
when my touran tdi reaches 90 on the dashboard it triggers high speed on the big fan. and sometimes it stops after a while, but sometimes it only stops when i turn my engine off. its so loud... so far replaced cts and thermostat but problem still there. tried triggering my fan with vcds and it only does high speed one. is it my low speeds burn out?
Possibly... we don't have the Touran here in North America. You need to check a wiring diagram to make sure you have not forgotten to check a fuse or low speed sensor / trigger.
It’s 91 vanagon gl Sorry i misunderstanding # 4 is ac fan control not radiator But i don’t hear radiator fan operate either My engine could overheat because Temp gauge keep raising so quick till blinking red light come up in about 5 mins since she started Please help
@@saranyukulsin1771 5 minutes is too quick for overheating... it's possible, but it might not be actual temperature. Can you check how hot the engine when temperature needle gets to 3/4 hot (shut engine off and check)? Remove the lower radiator grill and then disconnect the radiator fan switch (3 wire switch). One of the wires should have power all the time. Yes / no? Bridge the power wire with one of the other wires... fan should work. Yes / no? Do the same thing with the last wire. Fan should work. Yes / no? i.ytimg.com/vi/zmzk-h8QgAg/hqdefault.jpg
I have a vw jetta 1.8t and temperature sensor turns on seconds after I turn the car on. temperature reaches at normal 180. off course when I turn off the car and turn it back on the the temperature sensor doesn't come on and temperature is at the normal 180. do u know what is my problem?
You mean the red warning light? Have you checked the coolant level in the reservoir? If it is just below the minimum mark, that will turn the red light on... as the engine warms up, the coolant will expand and the level will be "above" the minimum mark. Turning the engine off and back on while the level is above minimum, will turn the light off. If you do not have a low fluid level, then I think there is some kind of electrical issue.
miguel calleja I have heard of coolant traveling up the sensor into the connector and then migrating along the wires into the main harness... causing electrical issues. I have not seen this happen myself, but have read about it. Pull the connector off of the bottle and check for wetness. Aside from that, keep monitoring it. If the needle ever goes too far past 180, don't ignore it!
Could be the FCM... but check all the power & grounds to it before you replace it. If you need a wiring diagram, let me know the year of the vehicle & engine etc.
Hey Thomas! in my car, 1.8t BAM engine the high speed never comes on. i bridged the pins and the high speed turned on, but it never turns on when driving, even if the car starts to overheat. i have changed the sensor, i've changed the FCM and still no high speed fans even if the water temp reaches 120 degrees Celcius. what is your guess?
alex brown If you turn the heater to max hot & blower to max speed... does heat get cold? If you bridge the rad fans to run all the time, does it still overheat?
hello i did the exact same thing u did on my jetta same exact results only high speed and no low like u tried there WHATS THE PROBLEM.... they wont come on when i turn the ac....please help
i have 07 jetta, i just installed new fan and my fan keeps running at all time. i have to disconnect battery in order for it to stop. as soon i reconnect battery, fan starts running. please help. !!
Did it do that before you installed the new fan? Which generation Jetta & engine? mk4 or mk5? If the fan has the "fan module" built into it... it could be in "always on" default, because of a wiring issue? Not sure.
Thomas EXOVCDS it didn’t do before. I replace with new fan because in old fan one of the blade was broke, causing it to vibrate. I have 07 jetta 2.5. As soon I plug the new fan into the harness, it went on and doesn’t stop unless I disconnect battery
If you still have the old one, plug that one back in and see if things change... you can do that from under the car, leaving the old one hanging... just to see what happens. Could be a fault with the new one (no communication with the ECM).
Thomas EXOVCDS I think New fan (both side)has stopped working completely. I think it blew the motor cause of constantly running at high speed. But I don’t get is why isn’t my car over heating? I drove almost 60 miles today and no sign of over heating on dash board
Hi My fans work in low speed (when I use the AC they do come on but they never work in high speed, what can it be? Is it possible that they just dont work in high speed?
You didn't tell me that... how was I supposed to know? Does low speed come on when AC is OFF? If no, then you have a thermostat or water pump issue. High speed is controlled by the Fan Control Module.
My high speed doesnt work. I changed relay resisitors it fixed my low speed but my high speed setting doesnt work. Even though it worked when i used a diagnostic machine and instructed it to?? Any ideas
Does the car have AC? What's the actual issue? Overheating? If low speed works, there should not be any overheating issue. Year, make, model, engine? The more info I have... the better I can guess what the problem might be.
Thomas EXOVCDS Yep my AC works. I have a Peugeot 2009 1.4 petrol. I keep getting warning messages, when checked with obd reader i got code P0692. My car overheats bc my high speed fan doesnt turn on. I have no idea where the issue is? Thanks for responding
Again, there should not be an overheating issue if low speed is working. There should be enough air flow through the radiator when the car is moving... if the engine is overheating when the car is moving, check the thermostat, water pump, coolant level, radiator. Do you have heat inside the vehicle? No heat can be due to a bad water pump. A bad water pump will cause overheating. We do not have Peugeot in North America... so I do not have any information that I can look up (wiring diagram or there service information). Sorry.
Thomas EXOVCDS The warning is read, "Fault in High speed control of the main fan Assembly Intermittent. Short circuit to earth". I have no idea what the fault means
I understand that you have a fault code. The engine should NOT overheat (at idle) as long as LOW speed is working. Does the car overheat while driving? Do you have heat inside the car? If the engine does NOT overheat while the car is moving, then yes, there is a problem with the fan (low & high speed).
I just did the timing belt, wp, thermostat, etc... on my B5.5 and when turned the key noticed that my radiator fan immediately went into HIGH speed. It also ran at that speed for the entire time the engine was running. With the engine off, the fan continues to run for several minutes but LOW. I am leaning towards the fan thermo switch as the culprit only because when I remember unplugging the wire harness from the lower thermo switch first then when I removed the lower hose from the thermostat housing coolant splashed onto the thermo switch's harness. After I was done I reconnected everything and started the engine. I'm thinking it might have shorted it. What do you think?
Thomas EXOVCDS I did and upon starting the engine the fan blew on low. But after about a minute cranked up to high. Now as soon as I turn the engine on it goes to high.
Thomas EXOVCDS I decided to pick up the sensor. I ran a test to rule parts out. I started the engine with the sensor plugged in. The fan came on full speed. I then disconnected the sensor and the fan shut off. Hopefully this takes care of the issue.
Thomas EXOVCDS So I swapped out the thermo switch and the fan is working fine now. But now I have a new issue. When i turn the heater on the AC clutch kicks on as does the radiator fan. I think I know what caused all this. I have an aftermarket HID kit installed for 2 years. This entire time they were sitting right behind the headlights, unmounted. So this weekend I secured them to some bolts in the engine bay. The passenger side right behind the light housing. But the drivers side one to the lower bolt that holds the washer fluid container......yup right next to the AC control module. This issue only occurred after putting the ballast in that location. I'm almost certain that was the problem because a month ago I placed the same ballast next to the ABS and guess what, I now have the ABS/ESP lights on. And.......now get static interference if I turn the headlights on while listening to the radio. I am getting a code for the ABS but nothing for the AC. Any ideas?
DIY Garage I watched it yesterday but did not get a chance to reply... I'm on vacation in Germany. Fuel pressure seems a bit high. I think it's a 4 bar system. 4 bar is about 60 psi. If pressure is too high, more fuel is injected and the system will run rich.
Thomas EXOVCDS I am really sorry during your vacation , can you tell me what could be cause of this high fuel pressure, I think my car most big problem is this
pelican parts dot com...lol Refers to the unit as: Control Unit - Fresh Air and Heater Control. Under Beetle 1999 and Climate Control Modules and Sensors section. Part # 1C0-820-045-E-01C-M211
I need more info... low speed is not working? Engine off, key ON, what happens when you manually bridge low speed & high speed at the radiator fan plug? Like this: th-cam.com/video/Roh6RCs8IJk/w-d-xo.html If low & high work when you bridge manually, but low speed does not come on by itself at idle, then the radiator fan switch (low speed circuit) is bad.
@@EXOVCDS yes Hi speed comes on when you bridge manually while on IDLE and low speed comes on when you bridge manually with car OFF, when the connector is on the radiator switch with the car on IDLE no fan spins at all, I was thinking they will only spin when the Coolant temperature is at 95° C, but my car hardly reaches these temps maybe due to sufficient air or great coolant. I have seen your Coolant replacement video and it looks like a job and a half, I will leave it at that since I don't experience any overheating of any sort.
You should be able to trigger low speed with key ON or OFF... high speed needs ignition ON if the vehicle has AC. If no AC, then you should be able to trigger high speed with key ON or OFF. Your TDI will take a long time to get warm, more so when the thermostat is opening early. Once the vehicle is moving, fans are not required. I would not worry about your fans as long as there is no overheating that needs to be addressed.
@@EXOVCDS yes there is no overheating at all I was amazed I drove it 140/160 KPH for 20 minutes and the needle never passed 90 degrees Celsius, The AC problem I had I found the problem it was the AC high Pressure sensor, I am still puzzled how a sensor with no moving parts involved just electrical signals gives in? I have ordered a new sensor and it should be here by next week, I hope once installed the compressor will start engaging and the fans will start spinning for AC cooling.
mronemanband1 Have a look at a mk4 wiring diagram and tell me how one resistor controls both fans. fkh161.ca/VW/radfans.png Both fans have individual resistors and both fans are triggered at the same time (by either the rad fan switch or the coolant fan control module).
@@relaxingnaturesounds9675 yes. The fan connector has 3 wires. The brown one is ground / negative. The other two are the ones that you will apply power to... from battery + (with or without a fuse). If one or both of the speeds do not work, replace the fan.
hey man i did the blower and ac. the fans came on. so what would make them not come on while it is driving? there is a.. kind of a whining noise coming from where the intake tube connects to the intake. I've never heard it before.
+Aaron Russell If the thermostat is stuck closed, the radiator fan switch (mounted in the radiator) will not get warm, due to no coolant circulation. Check the lower radiator hose to see if it gets warm / hot. If no, replace the thermostat (should be overheating as well if the thermostat does not open).If the hose does get warm / hot, then check the radiator fan switch for power (one of the switch wires should have battery voltage. One of the green fuses on top of the battery provides power to that switch. What year / model / engine do you have? Sorry if I asked that already (I can't keep track of all the posts that I reply to.
+Aaron Russell I just checked your earlier posts... 2000 Jetta VR6. You might be hearing the electric water pump (after run pump). It is normal for the pump to run after the engine is shut off.
Hey me again. So i was checking the bottom hose. it was always cold. but the temp never went past 190. and the fans never kicked on. but i ran it for about 20 minutes at idle. so it should have gotten hotter. i don't know if the temp gauge doesn't work after 190 or what. but it never got hot. but it should
+Aaron Russell My next step would be to check the temperature with a scan tool... to see what the engine computer "sees" in terms of temperature. If your only issue is that you don't hear / see the fans come on, just keep an eye on things for now.
+Thomas EXOVCDS Water pup has been replaced two months ago and I got a good quality one. The car reached 104°C (checked with vag-com, coolant gauge was at 90) so did not actually overheat I am worried by the fact that at this temperature fans did not start...
+scarablu1998 ' If lower rad hose is warm / hot, thermostat should be ok. Remove the harness plug from the rad fan switch and bridge the power wire (one of the 3 wires should have power all the time) with one of the others. Low speed should come on, if yes, replace the fan switch.... if no, low speed is burnt out on both fans. The 3rd wire is high speed and requires the ignition to be on. High speed is controlled by the fan module. Grab a wiring diagram and trace / check all the wires & fuses.
this is the link to the unit I was referring to. It's not working, the indicators on it are not coming on . By the way I wanted to thank you again: because of you video I was able to properly test both fans and fortunately they're working.
For clarification I am talking about the same plug on the fan that you have the wires in in the video. It is similar plug on the 2006 TDI Jetta but it has 4 tabs two large and two small with the wire colours as I described. I can take a photo of it today and send it to you. the plug has these cables leading to the large fan. Red large, Brn Large, Black small, Grn Small.
I got both fans on and turning the right way. Outside temp +25°C today above the 18° on the dial. I had to turn the Blower to 4 and turn off eco mode. Before all this I went through all the VAG settings and it told me that no Output test was available for this car TDI 2006 BRM Jetta. So there was no luck there. Then I tried the blower at 4 and re-leaved to see them turn on. Thanks for your help.
mronemanband1 Yeah, sorry... thanks for the info. This is one of my old videos where I did not go into detail. There are video pop-up annotations, but they only show up if the viewer has his/her annotations enabled. My newer videos have better lighting & text overlay... even some talking now and then. Thanks for watching and taking the time to comment!
I just attempted to turn on annotations. On my cell, option doesn't appear. On my PC, it was already enabled. So ... I never saw any annotations especially at the moment of testing into the connectors ... I'm curious where is the annotations normally displayed? I tried full screen and comment screen visible modes and never saw an annotation either way. ARE there any annotations for this video? THANKS!
@@christophermaxwell9621 Year, make, model, engine?
Follow this video to quickly check fan operation. Let me know your results:
th-cam.com/video/Roh6RCs8IJk/w-d-xo.html
Thanks for this video!! Exactly what I needed to find. I will check the fan operation tonight. Noticed that fans weren't operating at all 'cause my AC was intermittently blowing warm/cold air. Went through this 3 years ago. Replaced both fans and the FCM. Hopefully fans are ok. At least this time they spin freely, unlike last time. Thanks again! Oh, and the "let there be light" video, was HILARIOUS!!
I was gonna reply to the light comment, but then you posted this... also check the fuses on top of the battery (the green fuses). Thanks for watching & taking the time to comment!
***** I don't believe there are any fuses in that location for this year and model there are a few in the car but u haven't seen any under hood fuses
356gk T This video is for the VW A4 / mk4... not the Audi A4. The VW A4 does have fuses on top of the battery.
EXO While I have your ear. I have to say I think your videos are fantastic. In depth and really helpful. Fantastic Job. I will send you an email with the image of the plug.
hi thx for the video, I have a chev Caprice ..the engine fan does not work on high speed when the engine is running but when you connect it directly to the battery it works on high speed, we checked the fan relay both are ok, ... sometimes the car is overheating when in heavy traffic, the electrician suggested to connect both relay and to work on high speed only
Not familiar with Caprice... check the fans, fuses, thermostat, water pump and I'm sure you will find the problem.
Thank you so much for your prompt reply, do you think the fan speed problem (high and low) could be related to thermostat or water pump
+Its ShadeMan See my last reply.
Finally got time to mess with my car both low speeds were gone tested fan motors individually and only 1 fan had a high speed after I got it out but both were woking in car lol def bad fans. Replaced fan assembly fans working right again and it is possible to replace fan assembly without taking radiator out on an mk4 gti. its tough but doable i took the small fan out and put it back on shroud after i got it into position and mounted. The aftermarket fan assembly was larger than oem.
I used the 3 pin thermal switch connector to check mine. I believe the red wire is hot at all times. Jumping this wire to the other 2 pins will turn on both fans (one pin for high speed the other for low speed). High speed only works with the ignition on
Yes, good tip.... I like to check at the fan connector though, that way you know 100% that the issue is at the fan (if a speed does not work). You could have a break in the wiring between the fan switch & the fans or the fan module (for high speed).
I just did that and all my fans work by jumping can you tell me what to do next
Thanks
@Tim year, make, model, engine? Most likely (depending on the info you give me)... bad thermostat or water pump. Do you have heat inside the car?
@EXOVCDS thanks for getting back with me. 2001 golf GL 1.9 diesel tdi. I bypassed coolant fan switch and they both come on .and when I have car started and do the same fans come on.
Water pump works . Have decent flow at idle. Temp Guage never seams to work but if it idles for 20 or more minutes it moves to have way but no fans
I just tested my fans speed. To test Low speed test was good. I tried high speed but failed. I wanted to know if I could test high speed with middle ground and Red/White positive. I did your method as well (outer terminals) no power to high speed. Thank you for your great videos and your time.
Brown is ground... needs to be negative for both speeds. If you only have low speed and nothing happens when you attach the positive to the high speed wire, then high speed is burnt out.
Great video but which pin on the connecter do you put to ground
In responce to your Email. The Second smaller fan would not run when the AC was switched on. So I took out the fan and bench tested it. Smaller fan would not work and larger fan only works on high. a friend of mine at the dealer said that if one fan wasn't working it defaults to high on the main fan (maybe low isn't burned out.) So I changed the small fan. I am currently looking into how to do the VAG test. I will let you know how it goes. VAG gives me no error Code for the broken Fan.
First off The terminal has Red large, Brn Large, Black small, Grn Small. When I hook - black to Red on the plug they turn on reverse high (obviously +Red battery should go to Red on the fan) which is why reverse fan. But when I put -black on BRN and +red on Red I get nothing. Doesn't turn at all. Fan only turns when I reverse my leeds. Not sure why. I have to watch this in slow motion to see what you hook up to what lol.
Thanks for the prompt response. Would the hypothetically bad fans result in the control unit ( AC and Heater control) not working?
I have this same problem. Pulled out the fan and replaced the small one. Now I can get both running on high but not low. What is the right terminal hook up to get low. Power to both large runs high. Power from large to any small and no fan. (Also side note black attached to lead shown my fans also run reverse arrow. Reversing the leads won't run at all. Which is a bit odd.) What is the right terminal to get low running. Could mean my large fan has burned out low. Thanks great vid.
Thanks for the quick response! The Hanes Manual did the same thing. Told you run the jumpers to test the fan but did not indicate which one is which and of course the wiring diagram did not show it either. Keep the videos coming, I am allways working on my Jetta.
The one shown here is a 3 leed fan I have the 2006 TDI has 4 leeds in the plug. This shows 3 leeds looks like this but they changed this after this model. My old rabbit from the 80's and Golf from the 90's were like this too 3 leeds.
2006 is an A5 where this is an A4 in the video. There are some differences.
Thanks for puttng out all these great videos, saved me some time and money! Have a question..98 Beetle 2.0L, a/c does not blow cold air, replaced the fuse box on top of the battery(had the common burned fuse issue), a/c clutch does not engage, checked radiator fans low/high with jumper wires from thermo-switch(both worked), but fans do not run if I turn the car to ON and press the a/c button....do you have suggestions on next tests? Maybe an issue with fan control module?
Gene Thoman The A/C system needs to be pressure tested... if low on a/c charge, the system will not activate. A problem with the ambient temp sensor can also cause no a/c. A shop will not charge much to pressure test / recharge the system.
took it for a drive with new control module. radiator is red hot! still no fan. touched the hex of the fan switch and that was very hot! I may just have been unlucky and got a dud?
hi im get crazy with vw cnddy 1.9tdi... with key on fan run i replace sonsor ,,same problem,, i test swtich for coolant 2 pin with key on 5 v .i put led to battery + another led to coolant - come up 12 v its mean both is good ,,after that i test fan swtich 4 pin low speed high speed there is to power and 2 grown ,,,one of my grown wire is 9 v
is the sensor on the radiator the only switch for the engine being hot? also I disconnected my coolant temp sensor and it still picked temperature up on the gauge. I wanted to see as the wiring diagram I found had one wire from the ecm to the engine coolant blower motor relay. k12 on the wiring diagram. I can't find this on the car it's separate from the control module.
+MiniBikerUK Year of your 1.9 tdi ibiza? Maybe I can find a wiring diagram.
I have a 2004 VW Jetta 2.0 GL where both fan speeds operate fine manually but I have no low fan speed in auto mode. I have tried new coolant temperature sensor, new fan control module and new radiator temperature sensor and the engine temperature dashboard indicator climbs from the center position, (190°F) up pass two tick marks before the fans come ON in high speed mode. The cooling system is able to recover and come back down to the center position w/o triggering the overheating alarm. Why doesn't the low fan speed is activated?
Thank you in advance for your time and keep posting more helpful videos.
Disconnect the radiator fan switch (below the battery in the radiator), trigger low speed manually with a metal paper clip across the 2 wires in the radiator switch harness plug. Can you activate low speed like that? If yes, then the switch is faulty. Watch this video about faulty new sensors: th-cam.com/video/mlzDtTSHV6w/w-d-xo.htmlm
I can operate both fans low speed by jumpering radiator connector pins 1 to 2.
If I jump terminals 2 to 3 the manual tells me that I should get high speed and I do not, nevertheless they come ON at high speed in auto mode.
Ignition needs to be ON to activate high speed, since the Fan Control Module needs to be "awake". If you replaced the radiator fan switch already... it could be a bad switch. Does the lower radiator hose get hot as well? You might have a thermostat that is not opening fully.
I am going to follow uh our suggestion and place back the original radiator temperature switch and see what changes. Thank you for the helpful video link, keep up the good work.
Jose Sousa Let me know what happens! What was the original issue? Same thing? Running hot? No / little heat inside the car can be because of a bad water pump.
went to a local vw garage they suggested control module I got one cheap from a breaker. but obviously I can't guarantee it's ok .
have checked fans small one doesn't work motor is dead. still expect the other to kick in? so I replaced the switch. did a thermo too just in case as it was cheap. both pipes get hot when the car is sat still and not driving as when the car I driven the radiator cools it down? deaccelerating from hard driving brings the temp up to 110 and reached 130 once. but it was sat at 110 I opened the bonnet and no cooling fan
+MiniBikerUK Can you manually trigger the fan by bridging the thermo switch (in the radiator) connector?
Your a sharp smart dude...simple stuff first..but knowing what simple stuff is your smarts ...
+woody95124 Looking at some of my old videos, I question why I even bothered posting them (low light & no talking). I think my new videos have better lighting and the text overlay (instead of annotation pop-up like in this video) helps a lot. Thanks for watching & taking the time to comment. Oh, not so much smarts... more so common failure items due to age.
+Thomas EXOVCDS .its ok on oldervid..U move pretty quick!..but that's how u roll bud....How do you know which terminal is ground & hot to make fans work/...I 'am some sort of mechanic...not pro...I surely don't want to fry anything...thnx
woody95124 On VW & Audi, brown wires are ground. ALWAYS confirm with a wiring diagram before applying power & ground to be sure!!! The old systems such as this one are easier to troubleshoot.
okie doke....that's what allways has been for me ...the brn is allways ground....thnx!
Great video! Question:
Once you've determine that the fans our burned out on low speed what's the next step?
The control unit inside the car is not turning on and I did replace the bad fuse box on top of the battery.
didn't work with aircon anyway. Haven't tried taking it for a drive. should the fan kick in off the coolant temp switch and the radiator fan switch. of just fan switch?
+MiniBikerUK Mainly radiator fan switch... but depending on the system, the ECM or the Fan Control Module will turn it on when a temp sensor gets too hot.
i have a beetle turbo s 2003. the fans opperate on low but not high. ive changed the melting fuse block. also changed the large ac and fan controlor module, and all the temperature sensors on the car, even the fan switch in the radiator. do you think my high speed in the fans has burned out? they both run on low when i rumper the conector, but wont run when the high is contacted.
High speed bypasses the low speed resistor... so in theory, if low speed works, so should high. Watch the following video... do the same thing that I did AND record a video (so that I can see how & what you did). Post the video on your channel and then let me know when the video is up or post the link here. Also, use a test light to verify that power is getting to the high speed wires at the fan connectors.
I used a coolant flush and then ran a hose through it and it flowed well. or I thought it did anyway didn't seem any slower than the hose
Hey. I have a 2000 jetta with the vr6 2.8. the radiator fans quit and it blew my radiator. neither fan will work. could you write a walkthrough of what i should do first to see why they just quit. i could hear a motor like sound come from in the engine bay. it sounded like it was near the intake in the back. please help!!! thank you.
Thinking my fans are dead in my Audi A4 B6. I have the wires stripped up top to test the fans but don't know where to go from there. Blue and Orange wires come from one fan, then Yellow and Green to the other fan. Which color should I hook up to the positive? Is the correct way?
This video is for a VW A4 as in mk4 (4th generation) Golf or Jetta... your "Audi A4" is different. Your fans are "pulse width modulated" (turned on/off rapidly) by a fan module. Testing is different than in this video.
Also it's not feasible to test them up top, how do I make a jumper cable with a male pin it to test at the plug like in your video? Or can I just insert a twister wire in there? Never done this before.
You are correct, testing can not be done the same way.... you need to check for a "control signal" at the fan module. If Power & Ground are present at the fan module AND a control signal is present, then the fan module is bad.
Well I've already removed my fan control module to try to test my fans individually. I have two cable coming from each fan to the module. Purple and Orange from one and Yellow and Green from the other. What colors would be the power and ground?
Try it in either combination... if nothing happens, the fan is bad.
We did try them both ways and nothing, so both fans are dead then. Great! Haha.
Because they are "pulse width modulated" it is easy to burn them out... if they are manually activated for too long (hence the different testing method). If the fans did not do anything, yes, they are probably bad... common with age and especially on vehicles that constantly us the AC.
When I test at the thermo switch I get both on high speed but no low speed im going to have to try the other connectors to make sure it is the fans.
Hi Thomas. I have a problem on fans at my car audi a6, 2.7tdi,2009, engine CANA. when i switch ignition or star engine after 20 seconds the big fun run at full speed.it run all time and after switch off engine it shutdown after 30 seconds.i check fans manualy and work perfect. i have 2 errors:1. coolant fan control circuit 2:electric malfunction P0481. and 2. fan 1 control circuit: short to plus P0692. i visited more services and everybody say change both fans but i check them and its ok. Please help me with an idea what i can check? i check voltage on jack. i have 4 wires in jack. 2 big (+ and - permanently) and 2 small, 1 from ignition and apear voltage when switch ignithion and other one small which have 12-13v when fan run at high speed. Normaly on that wire i must have 1.2 when its close and 1.7-1.8 when start to run at low speed.(i check this on second fan from AC). Please help me!
The fan is controlled by the ecm... it should get an on / off signal. If there is a wiring problem, then the ecm can not control the fan. If the fan module is faulty, then the ecm can not control the fan. Disconnect the harness plug and look for an on / off signal on one of the wires. If one is present, then the fan / module is bad.
Your videos show good procedures but it would help if you could use more lighting to better view what you are doing. It's so dark that you can't really see much. Would also help if you add more narrative.
Eduardo Garcia Watch my new stuff. I can't change my old videos.
th-cam.com/video/Roh6RCs8IJk/w-d-xo.html
I tested my fans using the smaller 3 wire connector I saw another guy use in another vid, and only low works. Supposedly that means the fan relay module works, but if so then what doesn't work? could it be a resistor for high mode? both fans work on low neither work on high.
rpaull3 The Ignition has to be on for high to be triggered via the 3 wire connector (rad fan switch) in the radiator. What are your issues (if any)... overheating? A/C not cold enough? etc.
Thomas EXOVCDS hey i have the same problem, car overheats because fans won't turn on. I've tested the fans on low, they work fine but on high they don't work even with ignition turn on. What's the problem the FCM or the radiator thermo switch?
02 jetta fans work on low speed when ac on. Tested with jumper from the plug at radiator.only got low speed. Fans worked properly until i had the tranny and clutch replaced.
What's the actual issue? Overheating at idle... when cruising?
Actually my son's car but I believe it's both....going to try n rest fans tomorrow. I did notice that when I was checking power the motor was like magnetic to test light. Normal ?????.... But there was no issue with fans or cooling until tranny swap. Tested temps with laser rad was just over 100 n block was 200
th-cam.com/video/Roh6RCs8IJk/w-d-xo.html
Transmission / clutch removal should not impact fan operation. If you don't have heat inside the vehicle when heater is put to max hot, then the water pump is no good. Temperature gauge should stay in the middle... if it creeps to the right, then the thermostat is stuck or the water pump is not working. If the temperature does NO climb when the radiator fans are triggered manually, then the radiator fan switch is not working as it should (or the thermostat is not opening).
Sorry... if you DON"T have heat inside the car, then the water pump is no good.
Thomas on my seat 1.9 tdi asv engine 2001 if i start the a/c both of the fans start to work..but how can i tell if they're working on low or high speed?..what speed is normally engaged when you turn the a/c on?.. The low speed or the high speed?..if the low speed on the fan is burnt when i turn on the a/c will it engage directly the high one or will it stay still and not work?..
Andrei Ailoaie As far as I know (understand the wiring diagram) low speed is controlled by the radiator fan switch that is mounted at the side of the radiator. The high speed signal (from the radiator fan switch) goes to the Fan Control Module. The Fan control module turns on (I believe) the high speed (at a reduced speed) when A/C is selected. If the rad fan is fed power directly to the high speed wire, the fan spins faster than when A/C is selected (which leads me to think that the fan control module does some kind of speed reduction). I could be wrong...
***** i understand perfectly the explanaition..thanks a lot..best VW mechanic i ever met...hope they pay u well at work..good luck
low fan speed has burnt out so what does that mean new fans or new resistors? ive just noticed my 40amp strip fuse has blown on my mk4 golf and with air con on my low fan doesnt work.... which means its either the fans or the fan switch relay? any advice is highly appreciated
mathersooh If it's the resistor in the fan then the fan needs to be replaced. Test the fans with jumper wires if it is the same setup as in this video (bad lighting sorry). Each fan should have 3 wires. One brown & 2 red (with tracer colors). Attach the brown to battery negative and attach one of the red wires to battery positive. The fan should run at low or high speed depending on which red wire gets power. If you only have one speed (high or low), then the other speed is burnt out. We replace the fan... I'm not sure if it can be taken apart & repaired (I don't think so).
they might help slightly. I'm just struggling to get my head round it. wiring isn't my strong point
+MiniBikerUK Everything is labeled... if the fan works when you bridge the sensor & the radiator gets hot, then the sensor is no good. If the radiator & sensor do not get warm / hot, then something is preventing them from getting warm / hot.
hi thomas my wife has a 99 beetle with 2.0 gas AC works fine blows cold air and all but either fans are working i replaced both fans about a year ago they were working fine until now do you think it could have something to do with the fan control module thank you !
Follow / perform the steps in the following video. Let me know what the results are.
th-cam.com/video/Roh6RCs8IJk/w-d-xo.html
I recently replaced my radiator because it was leaking. I didn't take note of which fan harness connecter went to which when I took it out. I just reconnecting them assuming that it looked correct. Does the larger/smaller fan have to connect to a specific one?
They can only connect to one plug... the plugs are reversed / you can't mix them up.
Oh alright lol. Sorry I was a 6 pack deep at that point. Thanks for the response. Your videos have helped me out a bunch of times now.
I have an 01 A4 1.8 with AWM. The coolant temp gauge shows perfect temp while driving but after turning off and then restarting a few minutes later the temp shows one or two clicks above middle and then comes back down. The radiator fan runs fine but the aux fan only comes on when I run AC. Isn't the aux fan supposed to run based on coolant temp switch and after engine is shut off or is it possible the relays or module are bad? I just replaced timing belt, water pump, and thermostat and this started happening. Heater works fine. Ac always cold. No MIL and no other codes.
+matt audia4 Do you have an electric coolant after run pump? Might not be circulating coolant after shut-down. I'd have to check a wiring diagram to see what all ties together. Little fan should kick in when things get too hot... but is usually not needed, because things usually don't get too hot.
+Thomas EXOVCDS I don't think so. Just the fan on the left that is belt driven and the one on the right that is electric and comes on when the ac is running. I thought it should be also engaging based on coolant temp that the 4 pin switch senses (blue color on lower radiator hose) but I am not sure if that would be faulty or if there is something else I need to troubleshoot. I can't seem to figure out what is causing the temp gauge to show hot after a shutdown and restart.
+matt audia4 Like I said... if there is an electric water pump that is not circulating coolant after the engine is shut off... then engine temperature will rise. I'll have to check a wiring diagram... otherwise,l like I said, that fan should not need to come on unless temperatures climb... and yes, it should be triggered by a temp sensor or fan module (aside from AC switch).
Here is the problem in resistor. 1st speed going via resistor. When resistor blows does not working slow speed. I had this problem on Vw AG car (Seat Ibiza 6L)
Yes... resistor is inside fan motor.
Very good info !!!!
I have a problem... its a 2000 beetle the a/c not working - the compresor runs but the fans are out !! any hint on this please ?? we try a diferent radiator fan control unit and still the same problem ! one guy says its the fan swith !the triangular shape ?? but I dont know please HEEEELLLLPPPP !! BTW thanks for this tip !!
LOL :-/
hi i have an 04 audi a4 1.8t and when i bought it it came with cooling fans in the trunk with no control module and 1 of the fans wouldn't come on at all, so i got new fans and module at a junk yard my question is would there need to be coding to the new module with vag-com or not?
thank you
met rusani If it's out of a same vehicle, should be ok... be sure to keep an eye on engine temperature after installing. If it still gets hot and the fans don't come on, shut it off and check everything again.
ok thanks, i was just wondering cus ive seen people have to program abs modules.
Hey! Great vid! One question, my fans don't work on low speed (A4 VW Jetta) I installed a new Fan control module but no luck, do I need new fans? Thanks
Isaac Contreras I don't know... I usually test them (like in this video) to determine what works and what does not.
I have a 04 Jetta TDI 1.9 that was having a slight heating problem so I switch out the radiator fan assembly because I was hitting temps of 235 which is not normal for the car. Both fans for now but I'm still having an issue, my fans turn on when the car is turned off. Any advice? Thanks in advance
Could be electrical or a thermostat issue. The engine "should not" overheat while driving... if it does, it's not a fan issue. Check for correct coolant circulation / water pump operation as well as thermostat operation. Replace items as needed.
Thomas EXOVCDS I wouldn't exactly say overheat but abnormal temperature readings, it would normally stay around 190 or so now it gets up to 230-233 which is weird. But I'll make sure to look into it. Thank you
Hello, I have a 2007 vw Jetta that when I turn on ac the fans don't come on, when the engine gets to 190 degrees both fan will work. If is the fan could I jump the wires so will work when ac and heat is applied till I get the new one? It does get cold after the engine is at 190 degrees or I'm driving.
or how I could test the relay.
The AC blows cold air? What engine? I would have to check a wiring diagram to see what controls the fans when AC is pressed.
yes it does once the engine temp gets to 190, or I start drving. Is a 2.5.
HAROLD De La Matta I'll check a wiring diagram sometime today and will get back to you.
HAROLD De La Matta
The following AC pdf includes Automatic AC and Manual (use whichever diagram applies to your car)
fkh161.ca/VW/A5/mk5AC.pdf
The rad fan diagram is just for basic rad fan operation... which you know is ok.
fkh161.ca/VW/A5/mk5RadFans.pdf
If you have Automatic AC, check the system for fault codes... if manual, when pressing AC, the ECM needs to get a signal that AC was activated, so that it can trigger the fan module.
I think that with a scan tool, one can look to see if the ECM gets an AC signal.
Check all the fuses (powers) & grounds that are indicated in the pdf's.
Hi, I have problem with my fan. when I turn on the a/c after 20 or 30 min. the fuse (40 amp that is located on the top of battery) get burn and both fans are turned off also the compressor. both fans are news and I have changed 3 times the fuse. without a/c the big fan start correctly but I hear it too noisy, I think start in high velocity. I hope you can help me with this problem. thanks.
Hello, I have a 03 1.8t beetle , that the fans only work when the A/C is on.. I checked the low and high speed connector but only the low speed works.. is there something else I have to check or do I have to replace the fan.? Thanks.!
Is the engine overheating? Is it overheating when cruising (40mph)? Do you have heat inside the car (blower on MAX & Heat on MAX)?
+Thomas EXOVCDS.. yes heater inside blows hot, I replaced the thermostat also and hooked up my scanner since these cars come without a temperature gauge and the temperature gets up to 210 and the fans still won't kick on.
Did you check the green fuse / connection on top of the battery?
+Thomas EXOVCDS .. The fuse was good, I already tested the fan high and low spd and it works.. so that tells me that the relay and fans are good so I came to the conclusion that I have a bad thermo coolant fan switch.. possibly?I'm going to replace that and see what happens.
+Ernesto Madrigal Yes... sounds logical. Just wanted to be sure the thermostat & fuse are OK. if you have power at the fan switch plug, probably a bad switch.
Anyone have the diagram of the socket to know which end is the minus? Its oddly not showing for the MK4 jetta anywhere ive seen *yet* on the web.
Brown wire is always negative / ground.
@@EXOVCDS Thanks!
Well, then ... SOMEhow BOTH speeds of BOTH my fans are dead ...
AND the sockets TO the fans have a FRACTION of a volt ...
But all the fuses i can find are fine!
Bi-zarro!
So i got two more fans and that control box above the fan sockets at junkyard ... heeere we go!
Thanks!
(And how weird i cannot find that brown wire stated on any image for the socket on google images!)
@@fm2dmax I don't know how you are testing or here you are testing. Follow this video to check the fans via the radiator fan switch harness plug.
th-cam.com/video/Roh6RCs8IJk/w-d-xo.html
Post a video so that I can see your test results.
Hi thomas hope you're doing great ! i have a slight problem with my MK4 SDI , when i bypass the thermo switch (the triangular connector) i have only the first speed that works , but when i i try the second speed nothing happens , what should i check ? also note that when i remove the fuse N°16 from the fuse box , the fan doesn't come on at all ..any tips ? thanks a lot , enjoy your day.
2nd speed only works when the ignition is in the ON position... was the ignition on?
@@EXOVCDS thanks for takiing time to answer my question , well after switching the ignition to ON position the second speed kicks in ...but i was wondering why they don't work when i remove the fuse number 16 ?
@@mohamedbenbelkacem6121 I'll habeas check a wiring diagram to see why. I'll get back to you this weekend. What year is your mk4? Engine code ALH?
@@mohamedbenbelkacem6121 AC or no AC?
@@EXOVCDS the car engine code is AGP it's an NA version of an ALH ASV engine , it's an 98 MK4 Golf , and yes she got AC
Any help would be appreciated here is my issue: I have a 2001 audi tt with AWP 180hp AWD my car has two short to ground codes one is CTS short to earth and the other is fuel sending unit short to earth. My gauges in my car for both of them don't work at all and the cluster has been rebuilt. I have replaced the fan control module with no luck, next i have on order the fan temperature sensor, and also new fuse box for battery because my blade fuse going to the fans looks a little bent and the wire looked a little melted the red rubber. is there anyway to ground both of these manually if so can u tell me what wire to look for and how. please help im stranded.
sorry also i have replaced the CTS multiple times with no luck thanks
What I would do is use a scan tool... access the instrument cluster computer and then perform "output tests". If the gauges / needles do NOT move, then the problem is with the instrument cluster. If the needles DO move, then you have wiring issues. The CTS has 4 wires, 2 for the ECM and 2 for the dash... use a multimeter to check the wires for continuity / shorts to ground (ECM & ICM disconnected). You'll need a wiring diagram to determine where the wires are on the EMC & ICM connectors.
Thank you very much!!! Very useful video 👍
EmirFeliciano Thank you for watching & taking the time to comment!
Can't reply on my phone. checking your other video. I have flow. how ever my fan doesn't kick in with my ac. I have climatronic could that be related?
+MiniBikerUK Check your fan(s) manually. Fans will burn-out with age... especially when AC is used a lot (fans always running).
or possibly the new sensor is faulty would there be anyway of testing it?
+MiniBikerUK If you have an infrared thermometer / heat gun. Check how hot the sensor gets. If it does not get warmer than 97c to 110c, look for a radiator restriction. What year is your car... I'm trying to find a wiring diagram.
I have a vr6 mk4. the secondary water pump keeps working even when the car is shut off, and drains the battery charge, do you know if this issue has to do with the coolant fan module?
Good video by the way
Temperature sensor or fan module... me thinks. I'd have to check a wiring diagram if there are any other control devices that are part of that circuit.
Thanks, will check the sensors, probably disconnect one by one, and see if any of those is sending the signal. will let you know the outcome.
just replaced the fan module and the problem is still de same, the temp sensor was chanched about 6 months ago as well. will keep looking
Mark Rosas Golf or Jetta? AFP or BDF? Standard or auto? Manual ac or climatronic?
Hello Thomas EXOVCDS, 2001 Golf VR6 12V, manual transmission, climatronic, if the engine is 12 valves, i think is AFP, right? Thanks for the response.
I really want to do my electronic fan to manual swich, can you tell me where is the , electric fan relay and what number?
Year, make, model, engine? I can't read minds.
Thomas EXOVCDS
I am sorry, I mean , i want to start my cooling fan with switch (Audi A4 b6 1.8t amb quattro)(2003)
The wiring diagram I have doesn't show how many fans... how many fans does your car have? 2 electric or one belt driven with 1 electric?
According to this diagram, the fan module is controlled by the ECM... if you remove that setup... how are the fans triggered when AC is used? You'll also end up with cooling fan OBDII codes (with a check engine light in the dash).
fkh161.ca/Audi/A4/03AudiA4CoolingFan.pdf
Why not fix the issue... it's probably cheaper than trying to convert back to an older setup.
I have 2 electric one, so you mean if I install switch, I could be have trouble code?
If it’s turned on my engine check sign, than I am not gonna do it, but I want to know what situation my fan is turned on, because it some time on and some time doesn’t
You can see from the diagram that the fan is controlled by the ECM... the ECM keeps an eye on the engine temperature and then sends a signal to the fan module. You could have a bad fan module... check for fault codes. Using a scan tool, run output tests to see if the fans act-up (don't come on). If you have a multimeter, you can do some testing:
th-cam.com/video/oqdv4cm86Ns/w-d-xo.html
That video might not be the exact same as what you have in your car... you can use the wiring diagram I posted earlier, to check things.
Hey I have an 98 audi a4 1.8t and my engine is over heating cause my fans won't kick in to high speed I have Changed thermostat , coolent temp sensor..and I have checked the fuses any advice?
356gk T Do you get heat inside the car? If the heat disappears after a short while (even when set to max heat)... you either have air in the system or the water pump is broken / not pumping coolant.
***** I'm not getting any heat the car just keeps running until it over heats the second speed won't kick in I replaced the thermostat coolant temp sensor and 40 amp fuse all fuses and relays are fine I have not yet Checked 214 relay (cooling fan ) I read there is a thermo switch though could this be the problem?
356gk T if you are not getting heat inside the car, then the water pump is bad.
i really hope you can help me. I have a 99 vw 1.8t passat. I recently replace the head gasket because it was blown. It ran good for 6 months and blew again because it wasnt properly torque. So I replaced it again. It ran hot 10 days later. I notice that the AUX fan isn't coming on when its running hot. I replace the water pump, Coolant temp sensor and the coolant fan switch just last week. I replace the Aux fan relay also. It still runs hot after 10 mins of driving. I dont want to trash the car cause its my only transportation. I was under the impression that the fan switch controls the aux fan. its new and the fan still isn't coming on. I purge the air out the system the best I know how also. but still running hot. the temp light is coming on even when there is coolant in the expansion tank. Do you have any ideas. By the way the aux fan will come on when the ac is on.
Coolant light flashing when temperature needle is still within normal range? Is the viscous fan clutch working correctly?
+Thomas EXOVCDS no it flashes when over 190 but coolant is there. why is the coolant not doing its job. why the aux fan not coming on
i dont know if i should replace the whole fan assembly with new motors, replace the fan module, or what. really need help.
Key on engine off... turn the heater fan on and press the a/c button. Both fans should run... if no, check the fans individually for power. If power is present, replace the fans. if no power is present, check the green fuse on top of the battery. Run the engine and keep an eye on the temperature gauge. monitor the lower radiator hose temperature. if the lower hose does not get warm by the time the needle is just past center... replace the thermostat.
Ok I'll let you know what happens tomorrow. Thanks!
thank you for this video is a very big help for me
Thank you for watching!
Both of my fans work. But they both rev up to full speed on my 2.5 09 jetta, they start slow then rev up so I know both speeds work.
Your "fan control module" is part of the large fan. The ECM tells the fan module how fast to spin. Communication errors between modules, high ac pressure, or wiring issues can cause the fans to be on full speed all the time (fail safe). You need to check things.
th-cam.com/video/oqdv4cm86Ns/w-d-xo.html
So my vw jetta 1.8t i just put a new motor in it how do i check if my fans work my temp went to almost 260 shut the motor off but the fans didnt kick on what so ever when it idles it doesnt overheat
Follow this:
th-cam.com/video/Roh6RCs8IJk/w-d-xo.html
Let me know what you find / what the result of the test(s) was.
Definitely will i appreciate it , also i replaced my rear main seal and im really hopeing i dont have to do it again but noticed oil on the right side on my oil pain when i actually let it warm up by any chance would it seal off or do i have to take my transmission back off and flywheel and all that
In my 2006 audi a4 when I turn on car fan is loud n wen I turn off fan still stays on for abt 10 seconds wid the loud sound wat cud it e?
Scan for fault codes... loss of communication with the fan module can cause the fan module to turn the fans on at high speed. Could also be a temperature sensor issue or ac pressure sensor. Many things to check.
no it flashes when over 190 but coolant is there. why is the coolant not doing its job. why the aux fan not coming on
+Antwain Geffrard Not sure... how warm is the lower rad hose (going to the thermostat)? The viscous fan clutch should get stiff as the engine & radiator get warm... does it? Is the water pump belt tight? I believe this engine uses an external mounted water pump. If all else fails, can you take it to a VW / Audi repair shop for "diagnosis"?
The waterpump belt is very hard ane has cracks in it. I had a new one but haven't put it on yet. I didn't believe the belt would cause problems unless its slipping in the pulley
The lower rad hose doesn't get that hot
The fan with the clutch is the only fan that is on. I believe ita the mechanical fan it's called
I did this and the fan (if you're facing the car; no the left works but not on the right. I checked the fuses. But when the car warms up neither fan turns on and causes it to overheat. what would be your next step?
The car should not overheat if only 1 fan is working. If none of the fans come on by themselves, either the radiator fan switch is no good, the fuse is blown or the water pump is not circulating coolant. Do you have coolant flowing back into the coolant reservoir when the engine is running? Watch this: VW A4: Good Water Pump Flow at Idle You can remove the hose and point it into the top of the reservoir while someone revs the engine. If you do not have heat inside the car (even though the engine is warm / hot) that's another sign that the water pump is bad.
Okay, so I rerouted the fan to make one of them work, the other does not work. But I no longer believe the fan is the problem. I just replaced the radiator and bought new one (from autoone). It is still overheating. something I noticed is the bottom hose that connects to the radiator stays cold even when it's overheating..
Do you have heat inside the car? If no, your water pump is no good. If you have heat inside, then your thermostat is stuck closed. What engine is in your car? Have you checked for flow into the reservoir? Was it overheating before the radiator was replaced? Did the radiator blow because it was overheating before?
Okay a little back story, 2 thing's happened around the same time. Serpentine belt broke ( was 100 yrs from my destination so it didn't overheat. The pulley bearings went out and locked up causing the belt to break. I replaced both the pulley and belt. then the radiator was rusted and started to leak. so I replaced it. I got super hot heat. I just rerouted the fan to turn on with key ignition. it seems to be good when it's parked but when I drive it it overheats.
How do you check the flow into the reservoir
when my touran tdi reaches 90 on the dashboard it triggers high speed on the big fan. and sometimes it stops after a while, but sometimes it only stops when i turn my engine off. its so loud... so far replaced cts and thermostat but problem still there. tried triggering my fan with vcds and it only does high speed one. is it my low speeds burn out?
Possibly... we don't have the Touran here in North America. You need to check a wiring diagram to make sure you have not forgotten to check a fuse or low speed sensor / trigger.
What year? Engine code (ALH, BE etc)? I might be able to find a wiring diagram for you later.
My touran is basically mk5 golf and jetta
Vilius uk 2006 > ?
2005 pd engine. 77kw
My vanagon work on low speed #1,2,3 but not# 4 should I replace FAN RESISTOR WITH RADIATOR FAN WITH A/C ? Thanks
Radiator fan? I have only seen radiator fans with 3 speeds, not 4. sorry.
Can you give me more information? What year is the van? Is the engine overheating? Does your Van have A/C?
It’s 91 vanagon gl
Sorry i misunderstanding
# 4 is ac fan control not radiator
But i don’t hear radiator fan operate either
My engine could overheat because Temp gauge keep raising so quick till blinking red light come up in about 5 mins since she started
Please help
@@saranyukulsin1771 5 minutes is too quick for overheating... it's possible, but it might not be actual temperature. Can you check how hot the engine when temperature needle gets to 3/4 hot (shut engine off and check)?
Remove the lower radiator grill and then disconnect the radiator fan switch (3 wire switch). One of the wires should have power all the time. Yes / no?
Bridge the power wire with one of the other wires... fan should work. Yes / no?
Do the same thing with the last wire. Fan should work. Yes / no?
i.ytimg.com/vi/zmzk-h8QgAg/hqdefault.jpg
I checked
Fan work on high but not low
I have a vw jetta 1.8t and temperature sensor turns on seconds after I turn the car on. temperature reaches at normal 180. off course when I turn off the car and turn it back on the the temperature sensor doesn't come on and temperature is at the normal 180. do u know what is my problem?
You mean the red warning light? Have you checked the coolant level in the reservoir? If it is just below the minimum mark, that will turn the red light on... as the engine warms up, the coolant will expand and the level will be "above" the minimum mark. Turning the engine off and back on while the level is above minimum, will turn the light off. If you do not have a low fluid level, then I think there is some kind of electrical issue.
yes the red warning light. the coolant level is normal.
could you please tell me what could be the problem? and I will get a mechanic to fix it.
miguel calleja I have heard of coolant traveling up the sensor into the connector and then migrating along the wires into the main harness... causing electrical issues. I have not seen this happen myself, but have read about it. Pull the connector off of the bottle and check for wetness. Aside from that, keep monitoring it. If the needle ever goes too far past 180, don't ignore it!
sometimes I also notice a light white smoke come from the hood sometimes when I drive. temp is normal what could it be?
I can. I also managed to actuate it using a snap on scanner
+MiniBikerUK Weird then... maybe the radiator is not getting hot where the sensor is?
My problem is that when bridging, it does not activate high speed but low speed works. Will I have to change the FCM?
Ignition needs to be ON.... was it?
Yes, and still doesn't work
Could be the FCM... but check all the power & grounds to it before you replace it. If you need a wiring diagram, let me know the year of the vehicle & engine etc.
Hey Thomas! in my car, 1.8t BAM engine the high speed never comes on. i bridged the pins and the high speed turned on, but it never turns on when driving, even if the car starts to overheat.
i have changed the sensor, i've changed the FCM and still no high speed fans even if the water temp reaches 120 degrees Celcius.
what is your guess?
alex brown If you turn the heater to max hot & blower to max speed... does heat get cold? If you bridge the rad fans to run all the time, does it still overheat?
hello i did the exact same thing u did on my jetta same exact results only high speed and no low like u tried there WHATS THE PROBLEM....
they wont come on when i turn the ac....please help
low speed is burnt out. Replace the fans.
i have 07 jetta, i just installed new fan and my fan keeps running at all time. i have to disconnect battery in order for it to stop. as soon i reconnect battery, fan starts running. please help. !!
engine is not overheating. temperature gauge on dashboard stays in middle where it suppose to.
Did it do that before you installed the new fan? Which generation Jetta & engine? mk4 or mk5? If the fan has the "fan module" built into it... it could be in "always on" default, because of a wiring issue? Not sure.
Thomas EXOVCDS it didn’t do before. I replace with new fan because in old fan one of the blade was broke, causing it to vibrate. I have 07 jetta 2.5. As soon I plug the new fan into the harness, it went on and doesn’t stop unless I disconnect battery
If you still have the old one, plug that one back in and see if things change... you can do that from under the car, leaving the old one hanging... just to see what happens. Could be a fault with the new one (no communication with the ECM).
Thomas EXOVCDS I think New fan (both side)has stopped working completely. I think it blew the motor cause of constantly running at high speed. But I don’t get is why isn’t my car over heating? I drove almost 60 miles today and no sign of over heating on dash board
Hi
My fans work in low speed (when I use the AC they do come on but they never work in high speed, what can it be? Is it possible that they just dont work in high speed?
Its a vw beetle 2.0 1999
Thank you for all your videos!!! Specialy for all the vw beetles that you do.
When AC is on, both fans should run at low speed... high speed is only triggered when coolant temperature gets too hot.
@@EXOVCDS yes but when it gets too hot they dont turn on, they are both off.
You didn't tell me that... how was I supposed to know?
Does low speed come on when AC is OFF?
If no, then you have a thermostat or water pump issue.
High speed is controlled by the Fan Control Module.
My high speed doesnt work. I changed relay resisitors it fixed my low speed but my high speed setting doesnt work. Even though it worked when i used a diagnostic machine and instructed it to?? Any ideas
Does the car have AC?
What's the actual issue? Overheating? If low speed works, there should not be any overheating issue.
Year, make, model, engine?
The more info I have... the better I can guess what the problem might be.
Thomas EXOVCDS Yep my AC works. I have a Peugeot 2009 1.4 petrol. I keep getting warning messages, when checked with obd reader i got code P0692. My car overheats bc my high speed fan doesnt turn on. I have no idea where the issue is? Thanks for responding
Again, there should not be an overheating issue if low speed is working. There should be enough air flow through the radiator when the car is moving... if the engine is overheating when the car is moving, check the thermostat, water pump, coolant level, radiator. Do you have heat inside the vehicle? No heat can be due to a bad water pump. A bad water pump will cause overheating. We do not have Peugeot in North America... so I do not have any information that I can look up (wiring diagram or there service information). Sorry.
Thomas EXOVCDS The warning is read, "Fault in High speed control of the main fan Assembly Intermittent. Short circuit to earth". I have no idea what the fault means
I understand that you have a fault code.
The engine should NOT overheat (at idle) as long as LOW speed is working.
Does the car overheat while driving? Do you have heat inside the car?
If the engine does NOT overheat while the car is moving, then yes, there is a problem with the fan (low & high speed).
I just did the timing belt, wp, thermostat, etc... on my B5.5 and when turned the key noticed that my radiator fan immediately went into HIGH speed. It also ran at that speed for the entire time the engine was running. With the engine off, the fan continues to run for several minutes but LOW. I am leaning towards the fan thermo switch as the culprit only because when I remember unplugging the wire harness from the lower thermo switch first then when I removed the lower hose from the thermostat housing coolant splashed onto the thermo switch's harness. After I was done I reconnected everything and started the engine. I'm thinking it might have shorted it. What do you think?
Dry it off and see if it makes a difference.
Thomas EXOVCDS I did and upon starting the engine the fan blew on low. But after about a minute cranked up to high. Now as soon as I turn the engine on it goes to high.
I'm at work... will get back to you once I get home tonight. If that's all that happened (got it wet), replace the sensor and see if things change.
Thomas EXOVCDS I decided to pick up the sensor. I ran a test to rule parts out. I started the engine with the sensor plugged in. The fan came on full speed. I then disconnected the sensor and the fan shut off. Hopefully this takes care of the issue.
Thomas EXOVCDS So I swapped out the thermo switch and the fan is working fine now. But now I have a new issue. When i turn the heater on the AC clutch kicks on as does the radiator fan. I think I know what caused all this. I have an aftermarket HID kit installed for 2 years. This entire time they were sitting right behind the headlights, unmounted. So this weekend I secured them to some bolts in the engine bay. The passenger side right behind the light housing. But the drivers side one to the lower bolt that holds the washer fluid container......yup right next to the AC control module. This issue only occurred after putting the ballast in that location. I'm almost certain that was the problem because a month ago I placed the same ballast next to the ABS and guess what, I now have the ABS/ESP lights on. And.......now get static interference if I turn the headlights on while listening to the radio. I am getting a code for the ABS but nothing for the AC. Any ideas?
Can you please watch my new video? I want to know is that fuel pressure is good or not?
DIY Garage I watched it yesterday but did not get a chance to reply... I'm on vacation in Germany. Fuel pressure seems a bit high. I think it's a 4 bar system. 4 bar is about 60 psi. If pressure is too high, more fuel is injected and the system will run rich.
Thomas EXOVCDS
I am really sorry during your vacation , can you tell me what could be cause of this high fuel pressure, I think my car most big problem is this
Thomas EXOVCDS
What could be cause high fuel pressure?
pelican parts dot com...lol Refers to the unit as: Control Unit - Fresh Air and Heater Control. Under Beetle 1999 and Climate Control Modules and Sensors section. Part # 1C0-820-045-E-01C-M211
my high speed only works when the engine is on idle
I need more info... low speed is not working? Engine off, key ON, what happens when you manually bridge low speed & high speed at the radiator fan plug?
Like this: th-cam.com/video/Roh6RCs8IJk/w-d-xo.html
If low & high work when you bridge manually, but low speed does not come on by itself at idle, then the radiator fan switch (low speed circuit) is bad.
@@EXOVCDS yes Hi speed comes on when you bridge manually while on IDLE and low speed comes on when you bridge manually with car OFF,
when the connector is on the radiator switch with the car on IDLE no fan spins at all, I was thinking they will only spin when the Coolant temperature is at 95° C, but my car hardly reaches these temps maybe due to sufficient air or great coolant.
I have seen your Coolant replacement video and it looks like a job and a half, I will leave it at that since I don't experience any overheating of any sort.
You should be able to trigger low speed with key ON or OFF... high speed needs ignition ON if the vehicle has AC. If no AC, then you should be able to trigger high speed with key ON or OFF. Your TDI will take a long time to get warm, more so when the thermostat is opening early. Once the vehicle is moving, fans are not required. I would not worry about your fans as long as there is no overheating that needs to be addressed.
@@EXOVCDS yes there is no overheating at all I was amazed I drove it 140/160 KPH for 20 minutes and the needle never passed 90 degrees Celsius, The AC problem I had I found the problem it was the AC high Pressure sensor, I am still puzzled how a sensor with no moving parts involved just electrical signals gives in? I have ordered a new sensor and it should be here by next week, I hope once installed the compressor will start engaging and the fans will start spinning
for AC cooling.
For some reason I cannot post the link sorry
sorry didn't get a notification it's 2007/2008
+MiniBikerUK fkh161.ca/VW/AXRClimate.pdf
+MiniBikerUK Sorry... that might be wrong... one more coming in a minute!
+MiniBikerUK fkh161.ca/VW/AXRClimate001.pdf
my hero
Thank you for watching!
Nice !
Thank you for watching !
actually we didnt know where the problem is
Hey, buy a decent headlamp, and your work will be 100x times easier when no need for handheld torch ;)
That video is 2 years old... watch my new stuff.
th-cam.com/video/OvLP9ISYaoI/w-d-xo.html
mronemanband1 Have a look at a mk4 wiring diagram and tell me how one resistor controls both fans.
fkh161.ca/VW/radfans.png
Both fans have individual resistors and both fans are triggered at the same time (by either the rad fan switch or the coolant fan control module).
th-cam.com/video/px7FSdAAwlI/w-d-xo.html
Can you give me any suggestions with this?
I'll watch it later tonight after work.
Thomas EXOVCDS
👍🏻
Can I test the low and high speed of my cooling fan without using fuse on jumper cable
Yes... the fuse is just a safety that protects the jumper wires in case of short circuit.
I’m going to do this does it matter which cable has the fuse on it? And what gauge wire will work?
The fuse always goes on the power wire. Use similar size wire as is used by the fans.
Thomas EXOVCDS ummmm. Just one more dumb question and I’ll be done. What’s the power wire? Positive?
@@relaxingnaturesounds9675 yes. The fan connector has 3 wires. The brown one is ground / negative. The other two are the ones that you will apply power to... from battery + (with or without a fuse). If one or both of the speeds do not work, replace the fan.
I used a coolant flush and then ran a hose through it and it flowed well. or I thought it did anyway didn't seem any slower than the hose
hey man i did the blower and ac. the fans came on. so what would make them not come on while it is driving? there is a.. kind of a whining noise coming from where the intake tube connects to the intake. I've never heard it before.
+Aaron Russell If the thermostat is stuck closed, the radiator fan switch (mounted in the radiator) will not get warm, due to no coolant circulation. Check the lower radiator hose to see if it gets warm / hot. If no, replace the thermostat (should be overheating as well if the thermostat does not open).If the hose does get warm / hot, then check the radiator fan switch for power (one of the switch wires should have battery voltage. One of the green fuses on top of the battery provides power to that switch. What year / model / engine do you have? Sorry if I asked that already (I can't keep track of all the posts that I reply to.
+Thomas EXOVCDS it is a 2000 volkswagen jetta vr6 2.8.
+Aaron Russell I just checked your earlier posts... 2000 Jetta VR6. You might be hearing the electric water pump (after run pump). It is normal for the pump to run after the engine is shut off.
Hey me again. So i was checking the bottom hose. it was always cold. but the temp never went past 190. and the fans never kicked on. but i ran it for about 20 minutes at idle. so it should have gotten hotter. i don't know if the temp gauge doesn't work after 190 or what. but it never got hot. but it should
+Aaron Russell My next step would be to check the temperature with a scan tool... to see what the engine computer "sees" in terms of temperature. If your only issue is that you don't hear / see the fans come on, just keep an eye on things for now.
Hi, I have a 1.8t and the fans start only if i turn on the A/C, no matter how hot the coolant is they won't start...what could be the probem?
+scarablu1998 ' So it is overheating? Have you checked that the thermostat is opening and that the water pump is pumping coolant?
+Thomas EXOVCDS Water pup has been replaced two months ago and I got a good quality one. The car reached 104°C (checked with vag-com, coolant gauge was at 90) so did not actually overheat I am worried by the fact that at this temperature fans did not start...
+scarablu1998 ' If lower rad hose is warm / hot, thermostat should be ok. Remove the harness plug from the rad fan switch and bridge the power wire (one of the 3 wires should have power all the time) with one of the others. Low speed should come on, if yes, replace the fan switch.... if no, low speed is burnt out on both fans. The 3rd wire is high speed and requires the ignition to be on. High speed is controlled by the fan module. Grab a wiring diagram and trace / check all the wires & fuses.
+Thomas EXOVCDS I'm sure that low speed works because the fans start spinning when i turn on the A/C