Thanks, Your video goes to the basics. This has helped me very much with my old truck 😁. The explanation of how the whole system works and how it changes as AC is added, also how the temperature switch changes from grounded to not grounded. Thank you for sharing your knowledge!
Many thanks . . . this video was very helpful. Trying to trouble shoot prior owners electric fan wiring and this video helped me understand what they were likely attempting to accomplish. (Truck has two fan system, one 5 prong relay with 87a not used, both relay 86 and fan to run ground, 2 prong sending unit, relay 85 wired to both the sending unit and the A/C compressor). Appears they were trying to run both fans triggered by the A/C compressor but the compressor was being neurotic turning off and on every 5 seconds, which then would not get the fans spun up and car was running hot. Either this wiring is playing havoc on the A/C compressor or it’s a separate issue, but at least I can get my fans wired and running properly. Other videos that covered only a specific installation were not helping. But you covered it all here. Greatly appreciated!
I have a dual fan, 12.7amps each fan. Can I use a 15amp fuse inline from each relay to battery, or should I use a 30amp fuse and tie the battery leads together from both relays? Also wondering what size each relay should be. Great video!!!
If you want both fans to run at the same time. just ensure you have at least 12 gauge wire feeding them. Run both fans off one wire. Run a 30 amp relay and a 30 amp fuse. I personally run the 30 amp fuse in between the relay and fans, that way, if something over loads, it will pop the fuse before burning up the relay. Hope that helped.
Ty sooo soooooo much for shedding some serious light on this really helpful video. Wow I feel like it was taylor made for me lol. I couldn't find any one who could break it down and unpack it like you.👏🏾👏🏾🔥👍🏾💯
That is because brand vehicle is different. For my 1977 Chevy truck, I tapped onto the wire that powers the coil inside the distributor cap. But your vehicle is probably newer or even a different make, so therefore, my truck info will do you know good. I can help, tell me what kind of vehicle you have and I can look up where the best place it is you can tap into.
@@RodsshopOrg I have a 06 jeep wrangler and I can’t figure out a spot that powers up when the ignition is on. I was only finding ones when daylight running lights on. Also if I wire the fan to the switch they sent me then I can no longer tell my temp by my factory gauge right?
On the temperature switch, that will go in a completely different place. You leave the temp sensor for the gauge alone. I will look into a good place for you to wire off of. Contact me on my website, I may need some pictures of your engine compartment and it will be easier to communicate with you there. rodsshop.org/contact/@@riffraffchoppers
@RodsshopOrg how about on a 68 mustang 302. I've installed a painless wiring harness. I've used the extra accessories wire for the electrical fuel pump. Should I tap the pink ignition wire right behind the ignition?
Love the video. I have a 89 caprice I’ve done an Ls swap on and I want to run Ac. Whats the best to wire up the three relay to turn on the fan if the computer is controlling them plus what wire do I tie into to use a trigger to turn on the fans to come on when the ac is activated? Thanks if you can help
The best wire to tap into is the wire that engages the clutch on the compressor. Tap off that one to trigger the relay. I would stay away from trying to run relays that are controlled by the computer.
When we installed the new aluminum 4core radiator into the 99 civic hatch, we just spliced the fan into the original oem wiring guess still using the oem fan switch, is this still ok?
It should be, there shouldn't be any reason to rewire it. Just test it to make sure the fan kicks on and off like it should. If it does, then you're good
Great video.. I'm glad you included a 2 prong sensor..currently trying to figure out to add a manual override switch to my Derale transmission cooler..if you have an idea of how I could make this work I would appreciate it!
I have a 5 pin relay setup for mine as I run the fans in series and it switches to the ground that way if I run them in series it splits the 12 voltage to 6 volts of fan then one that other relay turns on it triggers that one off
In the video you said 10-12 AWG to the fan. I'm building a harness for an existing fan. The existing wire on the fan looks closer to 14. Should I connect a 10 AWG wire to the existing fan wire. Would it be able to hold the load without getting hot?
The main reason I recommended 10 - 12 AWG to the fan is because not everyone will be using the same fans. Most fans pull at max, 20 amps and usually that is the peak when the fan first kicks on. However, there are many performance fans that use 20 to 25 amps continuously. Since you are using an existing fan and it already had 14 AWG running to it, you should be safe to run 14 AWG again. 14 AWG wire runs up to 15 amps, 12 AWG is 20 amps and 10 AWG is 25 amps. If this is a factory fan, most of those use 14AWG, so just run that in your harness.
@@RodsshopOrg thank you. I used the formula watts divided by volts. With the fan only using 80 and the alternator running about 13.5 volts puts the current right under 6 amps. If I divided 12 volt it keeps the current under 6.7 amps. So I should be free running 16 AWG . THANKS FOR The clarification. I tried this a few times mixing wire so I just wanted to make sure I get it right this time. I've had problems with wires overheating. I'm using a 15 amp fuse because that was the original fuse used.
Thx for the video was very helpful! I have a question if you have the sensor in btw the relay which controls high n low speed single fan the color of wires are different on new plug the smaller gauge wires are the temp n a/c the 2 heavy gauge wires run off relay in fuse box it’s Jeep grand Cherokee Laredo how do I test or check the wires from harness to new plug the colors don’t match an gauge is all the same on new plug but have black 16 blue/red 16 and gray 10 blue 10 gauge idk how to share pic but it’s sensor under right head lamp plug ! Thx 🙏🏼
Contact me on my website rodsshop.org/contact-rodsshop/ Your question is a bit long and convoluted. One thing, there is no high and low speed on a cooling fan, it just turns on or off. This sounds like you are trying to hook up an aftermarket fan to the OEM equipment. None of what your saying makes a lot of sense but I think it is because I do not have enough information of what kind fan you are hooking up. So contact me through my website and I can provide you a way to upload me some pictures of what you have and what you are doing.
@@RodsshopOrg thank you! Everyone wants an does swap to Efan on 04 to 08 f150. 2010 fans fit flawless. But the clutch fan is pcm controlled it uses head temperature doesn't have a actual coolant
Thank you for uploading. Can I tap into the existing fan relay that is activated by a temperature switch so as to add a manual override, or do I have to use an additional relay?
Does this fan have wires for low speed and high separately? If so, download my wiring diagram for connecting the relay to run a fan and just do it again and tap into the wire that engages the clutch on the compressor be the wire that triggers the relay for the A/C
Hello. I am looking for a proper connection under the hood to run my 12v ignition wire. I have it directly to batt via relay but I am finding that doing it this way keeps the fans running after I turn truck off. Truck is a 90 silvy 350tbi. I have a toggle and wouldn't mind doing it that way.
Contact me through my website as you can send pictures through it as I may ask you to take some pics of certain things for me to help you find a connection. I normally don't like coming off the ignition wire that runs to the coil but that is a possibility. Lets talk through my site and I will help you: rodsshop.org/contact/
Yes, the toggle switch will just be used instead of a sensor. There is really no reason to ever use a 5 pin to setup a cooling fan, so a 4 pin is good.
@@RodsshopOrg okay i have 15 amp switch to relay with everything else wired correclty with 10g and 14g grounds and 30 amp fuse/holder and i still cant find the problem the only way it works for me to turn on and off the fan is when i wire 86 to 87 together onto pin 87 it works but then pin 86 is empty so im confuse on why is working like that?
Dope video, nothing I dont know but ADD makes me look things up a hundred times. Also had to rewind the clicking thru fans about 65 times...OK exactly 65 times lol, bit of OCD mixed in with a few energy drinks and SQUIRREL! SORRY, I'm back , great video, I just screengrabbed so I xan argue with myself tomoro installing 4 relays for low+high speeds/dual fan..until it turns into something else and I end up moving my seat bracket 1/4"+ running out of daylight instead
Hi, what would make my 30amp fused fan cooling relay to get extremely hot? but fan still working,my fan stopped working i found out it was down to burnt out relay so i got exactly same looking replacement relay from Amazon with 30amp fuse (probably made out of chinesium),it melted the fuse cover today but didn't made it pop,fan must have been running for few minutes while sitting in traffic so pulled over and disconnected it so it doesn't catch fire waited for it to cool down and drove it back home with eyes on the temp gauge and heater fans on max🤦♂️(none of the wires felt hot just relay) thanks
This could be a really complex question to answer based on a variety of factors. First off, what is the amperage draw on your fan? If it pulls like 25 to 28 amps, then that could cause the relay to get hot. The biggest thing I can think of that is overheating everything, is the wiring. What gauge wire are you running? How do you have battery voltage source feeding the relay? You should at least a 12 gauge wire coming from the actual battery or at least a great high amp source. It is also highly important that your ground wire to the fan is at least a 12 gauge and connected to an excellent ground source.
There is no speed control on fans, they are either on or off. The temperature sensor is really just a switch. When the sensor gets to the set temperature, let's say 190°, it turns the fans on, when the sensor gets cooled down, it turns the fan off.
@RodsshopOrg ok so my next question would you recommend higher Watts fans if it's not keeping my truck cool enough. Currently have 12v 90w dual fan but just getting on the freeway they don't stay as cool & after a while with the AC on it starts to overheat if the truck is stationary but on the go not really.
@@hase1357 I am guessing you have two fans since you said FANS. It isn't so much buying higher wattage fans, you need higher CFMs and there is a difference. I am helping someone right now on a Porsche that have super high wattage fans that requires a 70 amp fuse and blowing fuses and heating up wires. There is no point is jumping up wattage. Look at the CFMs and the wattage. A good fan will pull lesser wattage and deliver the proper CFMs. I know this may be a stupid question but need to address this first. Are you sure the fans are blowing the correct direction? Believe me, I have seen it all with electric fans. If the fans are on the engine side of the radiator, they need to be pulling in the air. If they are on the grille side of the radiator, they need to be blowing toward the motor. How big are the fans, as in what diameter? In all honesty, if the radiator is clean and flowing good, the thermostat is working correctly and is at the right temperature and the fan coolant temp sensor is turning on and off at the right temperature, most any fan is going to work. The only times I have seen where a fan isn't keeping an engine cool standing still, is if it is really too small in diameter or a real low CFM fan. If your fans are pulling somewhere between 1200 and 1300 CFMs, it should work. Get me the full specs on the fan. Go to my website and contact me through it so I you can email me some pictures of your setup and I am sure I can help you. rodsshop.org/contact/
@@hase1357 you can control the fan speed with pwm the Ford Taurus and fusions are the easiest cars to get a pulse width modulated box aka pwm in short it cuts the ground on and off on and off for a pulse which controls speed but the Ford have them on them that way for a dual setup you can have both fans on but lower speeds and then both on for high
Which sensor currently on the truck do you have to remove in order to use the sensor switch that comes with fan? The temp or sending unit? They both have 5v signal, the new sensor is to be grounded so they can't go together right?
You need to be more specific, are you putting an electric fan on a vehicle that already has one? If not, there is no sensor to remove, you are adding one. Any other temp sensor that is already on the vehicle is for a light on the dash or gauge and you do not remove those. Please contact me through my site and explain in detail and send me pictures of what you are doing. rodsshop.org/contact/
I am not sure what you are asking. Relays are measure in amps, so if you have a fan or component that you know is going to draw 22 amps, it would be safe to get a relay that can handle up to at least 30 amps. If you need help on this, you will need to give me more information on what you are trying to do.
Really wish you could have showed a real hook up step by step, I get 30 goes to the battery and 87 goes to fans positive wire, the other 2 85 and 86 im so confused on, and where does the ground for the temp switch in the radiator connect to? I have it connected to the cross bar over the grill, and what about the black wire from the fan? Too many things I need visuals of to get this to work.
These instructions are pretty clear but also depends on what you are working on and your situation may be different. Contact me through my website, that way you can send me pictures and I can help you get what you are doing setup, I am here to help. rodsshop.org/contact/
@@RodsshopOrg oh I hooked everything up right just as you said, and it still dont work so idk anymore its ridiculous. 30 goes to circuit breaker, 2 bolt mechanism basically, connects to aux side then a wire runs from the stud labeled bat to the battery so that should feed a continuous power feed from the battery, the switch is just a substitute for in line fuse from what i understand. 87 ran to the power wire on the fan, 85 and 86 ones running to the temp sensor that's in a housing that is installed on my upper radiator hose, I have a ground wire running from it to my engine block and then the other I have connected directly to the positive side of the battery instead of an ignition power cuz it really don't matter as long as there is power from what I saw on other videos, my car is not going to exceed 210F just sitting in my drive way. So I don't know what else to do, I tried a different relay just to make sure it wasn't bad still don't work, monitored the engine coolant through my obd2 and it just climbs past 210 and nothing happens. Lot of vids say it dont matter which you use for each on 85 or 86 because it's DC and just a means to complete a circuit. Can you see anything I may have wrong there? I'll see what I can figure out on your website tomorrow I'm beat, and done messing with it for today. Just too frustrated right now.
@@bentramell729 This would be easier to help you through emails as I could send you a diagram to simplify this but from what you have wrote, I think the issue is your 85 and 86. All these two pins do is energize the relay, so as you found out, it doesn't matter which one is positive or negative but from what I read you wrote, and maybe I misunderstood it. But it sound like you have your temperature sensor trying to switch 85 and 86 together and that would be wrong. You need to add power lets say to 86. I usually make this a wire that only has power when the ignition switch is in the on position. Then 85 would go to your temp sensor. The temp sensor has to be grounded, so if you have it in a housing inline with the radiator hose, you have to run a ground wire off the housing to the engine block or some good ground. When the sensor gets to the designated temperature, it then grounds the wire that goes to 85 and energizes the relay which then sends power through 87 to the fan. Please, if this doesn't work or make sense, contact me through my site, I am not going to use your email to spam you, it is just email makes sending pictures back and forth so much easier.
@@RodsshopOrg no it makes sense it's what I've done, I have 1 of the wires, 85 or 86, not sure which but one of them is running to the temp sensor in the housing inlayed in the upper radiator hose, the other one is running to the positive post on my battery. I have a ground running from the temp sensor housing to the engine block. 87 running to my fans positive wire, fan is grounded. 30 runs to the circuit switch and then from the circuit switch to the positive on the battery. It should work I don't understand why it dont. I've tried two different temp sensors and 2 different relays and still nothing. I don't think my problem lies with not being hooked up right but rather or not my wires have proper connection or maybe my radiator fluid was too low not really reaching the temp sensor inside the hose and just passing under it. It's a head scratcher though. I won't bother you anymore, I appreciate you talking this out with me but im certain I have the schematic of it hooked up correctly there's just something else that's not right, idk maybe my ground from the housing to my engine block isn't in the right place, I did have it on the crossbar over the radiator where the hood latch is at like I saw other videos with this same set up put theirs and it worked just fine on theirs that way and didn't have to be on the engine itself. Maybe my circuit breaker is bad and not translating power like it should on 30. Lots of variables that are going to be difficult to test.
@@bentramell729 Before you give up, go back to the basics. First off, you may want to watch my other video on relays: th-cam.com/video/5wVeCYuDJuI/w-d-xo.html Going back to basics means, ignore all the switches and sensors and just run wires to the relay to see if you can trigger it. I have another video where I put electric fans in a truck. Here you can see how I just ground the wire going to the sensor to trigger the fans to kick on. th-cam.com/video/W5Ucc63uvn4/w-d-xo.html You can see me go around the sensor at time stamp 36:12 Contact me through my site, send me pics of your setup and I can get you going
Sounds like the sensor wasn't grounded good and created a current overload. Or you do not have it wired correctly. The power on the sensor is supposed to be low, all it does is turn the relay on and off. If you have the sensor switching the full amperage to the fans, this will melt everything. Are you sure you have it wired correctly? I ask because even if the sensor isn't getting a good enough ground, the current should be so low on it that the most could happen is it doesn't switch the relay. I can help but contact me through my website so you can send pics of what you did. rodsshop.org/contact/
Recently got an LS3 Swap. Exactly what I was afraid of happened. Shipped it to another state to the expert and now I’m having issues and we are trying to figure it out over the phone. Started with over heating. Found one of dual fans stop working because fuse melted inside its inline wire case. Fans are wired to be on as soon as I turn key to on. So I replaced inline fuse wire and 40Amp fuse. Now after 10 minutes of fan running relay so hot you can barely touch it. So I swapped the relays and the one getting hot didn’t get hot anymore but the new one on the side with fan issues did. The installer is sending me a new relay, he says the base the relay connects to can be bad, but I just don’t see how. But everything is possible. Today when I get home I’m measuring the resistance of each fan. Hopefully I don’t have to cut any wires to do this. Any advice?
This is probably a bit much to try and discuss in this comment section, so talking through my site might be better. rodsshop.org/contact/ It sounds like you have a bad fan more than anything. You need to measure the amp draw, (the current) for the fan in question. I would run jumper leads off the battery to run the fans outside of the fused and relayed wiring. Use a volt ohm meter that can test amps and run it in between each fan. I would measure the amps on the fan that you know is working fine first. That will give you how many amps it should be drawing. Then test the fan in question. Be sure to check the ground on the fan in question. A bad ground will cause it to pull more amps but no fan unless it is huge should be pulling more than 20 amps. So if you had to run a 40 amps, you are just waiting for a fire. Check the current draw before going any further. Contact me through my site and let me know what it all said and I will try and help you through the rest.
If I have a trunk mounted battery do I need to run the power wire all the way to the trunk or could it go to a constant power source in the engine bay somewhere like the starter relay?
There should be a junction under the hood where you can hook jumper cables to if you ever need a jump start. Look for it and you can just run power off of that.
Then yes, just come off that terminal for your main fan power and that should work just fine. Just be sure to use the appropriate gauge wire for the amp draw of your fan. I would run no less than 12 gauge if this is a more common fan that doesn't pull more than 15 to 20 amps when it first starts running.
Any regular 4 PIN relay is always open. This is shown in the video, PINS 30 and 87 are open until you add low current to PINS 85 and 86. This is going to be the same on all amperage rated relays.
I am not sure what a prog is. If you are talking about that housing that the temp sensor goes into, it does have a ground wire to the housing and it can be run to the engine block. If am answering that wrong, let me know and I will do my best to help you.
I hooked up my fan to a led light bar harness, and it’s not spinning as fast as it was hooked up directly to the battery, the relay is a 40a and fuse is 30a, what can I do to get the fan to spin faster?
You need to go to a heavier wire. LED lights are low amp wire, the fans need at minimum a 14 gauge wire, I prefer 12 gauge. More than likely, the LED Bar wires are 16 or 18 gauge wire and that isn't heavy enough to run fans. @josebuenrostro9080
Yes, 12 gauge would be best. Also ensure that all your wire connections are good, as a bad crimp or connector not making good connection can also cause your fans to run slower. @@josebuenrostro9080
@@RodsshopOrg I put 10 gauge and everything is looking good but when I flip the switch it feels like my truck is gonna die from the current draw but it picks back up since I upgraded my alternator, would you suggest I get a new battery as well?
How old is the battery and what cranking amps is it? If you beefed up the alternator, that should be enough. Just how many amps does your fan pull and how many fans do you have? @@josebuenrostro9080
Run the ground wire to the radiator support or even to the negative battery cable. Just ensure that it is metal that is fully grounded. You can use a multimeter to check ohms between the negative battery post and what ever you are going to ground your fan to. Just make sure there is no resistance, if not sure, run a wire off the negative battery post to the radiator support to ensure it is grounded.
hello there I have a 1999 Isuzu order, I need to wire a trans cooling fan, I want it to come on when I start the car and stay on untell I turn the car off. what can I wire pin 85 to so that it will have power when I start the car?
You just need an ignition wire, check for any wire that becomes hot when you turn the key on. I do not remember on your vehicle off the top of my head if it has a coil pack or some form of an ignition control box, but any wire to these type of devices you can use to trigger your relay. If you need help, you can always contact me through my website and I will do my best to guide you. rodsshop.org/contact/
@@williamtreat5893 Yes, if you can find a fuse that gets 12 volts only when the ignition key is on, then you can tap off that. You can also tap off the alternator, not the main wire that charges the battery but the one that engages the alternator. You will need a volt meter or test light but either should supply you the voltage you need whenever the ignition key is on.
@@RodsshopOrg first let me tell you that I'm wiring a trans cooler temp sensor and it will be going inline between two rubber hoses-the temp sensor has two pins sticking out of it, so I wire one of them to pin 85 - that's the wire that has power only when the car is running right? so when the temp sensor reaches the temp it will send power to pin 87 and tell the fan to turn on right? do I wire the other pin from the temp sensor to pin 86-for a ground? you did say at the start of the video that pin 86 could be used as a ground or do I need to wire it somewhere ells? and NOT to a ground- the little metal bracket on the back of the relay where you mount it to the firewall is that not a grounding point? i just don't know where to wire the second pin from the sensor-you would think that if one pin was hot and the other pin was a ground when it activated the hot and ground wires would be an electrical problem
I am not clear what you mean fan controller. Are you talking about the switch on the dash or are you talking a control that can vary the speed of the fan. Please clarify...Thanks
@@RodsshopOrg I'm sorry I have a flex a lite fan controller on 2 derale 12 inch fans and I wanted to run some relays to reduce the load I have them on the controller and one 50 amp fuse and the fuse gets hot
If you are wanting to hook up a temp gauge off the sensor that triggers the fan, it won't work. The sensor that triggers the fan is basically a switch and will not operate a temp gauge. You will need to find another port in a head or block or even the radiator to screw a sensor designed to run a gauge. I am not sure if this answers your question if not, let me know if I have misunderstood.
30 amp but for you, it is going to depend on what you are running. You need to check the amperage draw on your fans or whatever device you are going to be running. But in most cases, a 30 amp breaker should be enough to run cooling fans.
I installed a dual fan in my 86 c10. Installation was painless. The issue I have is once the temp rises and the fans kick on they don't kick off. Could this possibly be a bad relay? Thanks in advance
It could possibly be that your temp sensor for the fans is a less temperature than your thermostat. In other words, if your thermostat is a 190 degree and your sensor for the fans is 160 degrees, the water temp is never going to get below 160 to shut off. I am guessing the fans turn off after the engine cools off, you may need to give me more detail.
@@RodsshopOrg I utilized the temp sensor that came with the kit and installed a 160 thermostat as well. The only thing I did different from your wiring video is the key switch and the temp sensor are reversed. So at the moment the white wire is tied into a key switch source and the black wire is tied into the temp sensor sending unit. Due to following another how to video.
Well maybe most people are not as diligent as you to remember to turn on the fan when the engine starts to get hot. Most people do not want the fan to run all the time nor is there a need for the fan to run all the time. We are in the 21st century, so most people want things to be automatic. But if you are happy just turning on a switch and remembering to turn it off, then I say go for it. This video is if those that want to hook up a relay for any item if you want to, not that you have to.
I have 1998 Oldsmobile cutlass GLS 3.1 my fans will engage if I turn the AC on. I changed fan relays fans are not turning on by their self when just idling at a red light it will go over half and start to overheat. Replace water pump thermostat and flush. I’m still overheating If I sit at a red light too long?
Sounds like the temperature sensor isn't working, there is ways to test that. Contact me through my website so I can help you. It is just too hard to communicate through TH-cam comments, we may need to share images. I am not going to spam you. rodsshop.org/contact-rodsshop/
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Nice job of describing all of the components and how they work together. One of the better videos I have seen. Thanks.
Thanks, Your video goes to the basics. This has helped me very much with my old truck 😁. The explanation of how the whole system works and how it changes as AC is added, also how the temperature switch changes from grounded to not grounded. Thank you for sharing your knowledge!
Thanks for sharing your knowledge you are a special person and a great teacher
I am glad my video could help.
Many thanks . . . this video was very helpful.
Trying to trouble shoot prior owners electric fan wiring and this video helped me understand what they were likely attempting to accomplish. (Truck has two fan system, one 5 prong relay with 87a not used, both relay 86 and fan to run ground, 2 prong sending unit, relay 85 wired to both the sending unit and the A/C compressor). Appears they were trying to run both fans triggered by the A/C compressor but the compressor was being neurotic turning off and on every 5 seconds, which then would not get the fans spun up and car was running hot. Either this wiring is playing havoc on the A/C compressor or it’s a separate issue, but at least I can get my fans wired and running properly.
Other videos that covered only a specific installation were not helping. But you covered it all here.
Greatly appreciated!
Awesome, glad I could help you out!!
Really clear, well explained - very helpful 🤛🏻
I have a dual fan, 12.7amps each fan. Can I use a 15amp fuse inline from each relay to battery, or should I use a 30amp fuse and tie the battery leads together from both relays?
Also wondering what size each relay should be.
Great video!!!
If you want both fans to run at the same time. just ensure you have at least 12 gauge wire feeding them. Run both fans off one wire. Run a 30 amp relay and a 30 amp fuse. I personally run the 30 amp fuse in between the relay and fans, that way, if something over loads, it will pop the fuse before burning up the relay. Hope that helped.
Great info. Thanks!
Ty sooo soooooo much for shedding some serious light on this really helpful video. Wow I feel like it was taylor made for me lol. I couldn't find any one who could break it down and unpack it like you.👏🏾👏🏾🔥👍🏾💯
This is the most informative and easy to follow video, thank you!
Glad I could help
Iv watched 20 of these videos and not one single person yet has gave an example of what wire you can tap into for the ignition hot wire
That is because brand vehicle is different. For my 1977 Chevy truck, I tapped onto the wire that powers the coil inside the distributor cap. But your vehicle is probably newer or even a different make, so therefore, my truck info will do you know good.
I can help, tell me what kind of vehicle you have and I can look up where the best place it is you can tap into.
@@RodsshopOrg I have a 06 jeep wrangler and I can’t figure out a spot that powers up when the ignition is on. I was only finding ones when daylight running lights on. Also if I wire the fan to the switch they sent me then I can no longer tell my temp by my factory gauge right?
On the temperature switch, that will go in a completely different place. You leave the temp sensor for the gauge alone. I will look into a good place for you to wire off of. Contact me on my website, I may need some pictures of your engine compartment and it will be easier to communicate with you there.
rodsshop.org/contact/@@riffraffchoppers
@@RodsshopOrgemailed you
@RodsshopOrg how about on a 68 mustang 302. I've installed a painless wiring harness. I've used the extra accessories wire for the electrical fuel pump. Should I tap the pink ignition wire right behind the ignition?
Spectacular presentation and explanations. Answered some questions that were very hard to find concise answers to
Love the video. I have a 89 caprice I’ve done an Ls swap on and I want to run Ac. Whats the best to wire up the three relay to turn on the fan if the computer is controlling them plus what wire do I tie into to use a trigger to turn on the fans to come on when the ac is activated? Thanks if you can help
The best wire to tap into is the wire that engages the clutch on the compressor. Tap off that one to trigger the relay. I would stay away from trying to run relays that are controlled by the computer.
When we installed the new aluminum 4core radiator into the 99 civic hatch, we just spliced the fan into the original oem wiring guess still using the oem fan switch, is this still ok?
It should be, there shouldn't be any reason to rewire it. Just test it to make sure the fan kicks on and off like it should. If it does, then you're good
@@RodsshopOrg yeah, fan kicks on and off like it did before new rad install.
Great video.. I'm glad you included a 2 prong sensor..currently trying to figure out to add a manual override switch to my Derale transmission cooler..if you have an idea of how I could make this work I would appreciate it!
I have a 5 pin relay setup for mine as I run the fans in series and it switches to the ground that way if I run them in series it splits the 12 voltage to 6 volts of fan then one that other relay turns on it triggers that one off
In the video you said 10-12 AWG to the fan. I'm building a harness for an existing fan. The existing wire on the fan looks closer to 14. Should I connect a 10 AWG wire to the existing fan wire. Would it be able to hold the load without getting hot?
The main reason I recommended 10 - 12 AWG to the fan is because not everyone will be using the same fans. Most fans pull at max, 20 amps and usually that is the peak when the fan first kicks on. However, there are many performance fans that use 20 to 25 amps continuously. Since you are using an existing fan and it already had 14 AWG running to it, you should be safe to run 14 AWG again. 14 AWG wire runs up to 15 amps, 12 AWG is 20 amps and 10 AWG is 25 amps. If this is a factory fan, most of those use 14AWG, so just run that in your harness.
@@RodsshopOrg thank you. I used the formula watts divided by volts. With the fan only using 80 and the alternator running about 13.5 volts puts the current right under 6 amps. If I divided 12 volt it keeps the current under 6.7 amps. So I should be free running 16 AWG . THANKS FOR The clarification. I tried this a few times mixing wire so I just wanted to make sure I get it right this time. I've had problems with wires overheating. I'm using a 15 amp fuse because that was the original fuse used.
Thx for the video was very helpful! I have a question if you have the sensor in btw the relay which controls high n low speed single fan the color of wires are different on new plug the smaller gauge wires are the temp n a/c the 2 heavy gauge wires run off relay in fuse box it’s Jeep grand Cherokee Laredo how do I test or check the wires from harness to new plug the colors don’t match an gauge is all the same on new plug but have black 16 blue/red 16 and gray 10 blue 10 gauge idk how to share pic but it’s sensor under right head lamp plug ! Thx 🙏🏼
Contact me on my website rodsshop.org/contact-rodsshop/
Your question is a bit long and convoluted. One thing, there is no high and low speed on a cooling fan, it just turns on or off.
This sounds like you are trying to hook up an aftermarket fan to the OEM equipment. None of what your saying makes a lot of sense but I think it is because I do not have enough information of what kind fan you are hooking up. So contact me through my website and I can provide you a way to upload me some pictures of what you have and what you are doing.
Can you use an electric clutch fan oe harness for the signals?? That would keep factory specs an temp sensor in theory?? 2007 f150
I am not clear whet you mean electric clutch fan.
@@RodsshopOrg Like on my 2007 5.4 F150 it has an electronic clutch fan
@@JokersHangout I will look into this and get back to you
@@RodsshopOrg thank you! Everyone wants an does swap to Efan on 04 to 08 f150. 2010 fans fit flawless. But the clutch fan is pcm controlled it uses head temperature doesn't have a actual coolant
Thank you for uploading. Can I tap into the existing fan relay that is activated by a temperature switch so as to add a manual override, or do I have to use an additional relay?
You can tap into an existing relay, no need for another one.
Great video..
Could you tell me how to wire up a single 2 speed fan, to run for a/c and temp.
Does this fan have wires for low speed and high separately? If so, download my wiring diagram for connecting the relay to run a fan and just do it again and tap into the wire that engages the clutch on the compressor be the wire that triggers the relay for the A/C
Thank you
Hello. I am looking for a proper connection under the hood to run my 12v ignition wire. I have it directly to batt via relay but I am finding that doing it this way keeps the fans running after I turn truck off. Truck is a 90 silvy 350tbi. I have a toggle and wouldn't mind doing it that way.
Contact me through my website as you can send pictures through it as I may ask you to take some pics of certain things for me to help you find a connection. I normally don't like coming off the ignition wire that runs to the coil but that is a possibility. Lets talk through my site and I will help you: rodsshop.org/contact/
Great video and information! Thank you!
what about a toggle switch will a 4pin still work on and off for a radiator fan?
Yes, the toggle switch will just be used instead of a sensor. There is really no reason to ever use a 5 pin to setup a cooling fan, so a 4 pin is good.
@@RodsshopOrg okay i have 15 amp switch to relay with everything else wired correclty with 10g and 14g grounds and 30 amp fuse/holder and i still cant find the problem the only way it works for me to turn on and off the fan is when i wire 86 to 87 together onto pin 87 it works but then pin 86 is empty so im confuse on why is working like that?
@@RodsshopOrg or can i just run just a s witch with a fuse to the fan... fuck all the relay shit i keep having problems ive wired it all types of ways
Dope video, nothing I dont know but ADD makes me look things up a hundred times. Also had to rewind the clicking thru fans about 65 times...OK exactly 65 times lol, bit of OCD mixed in with a few energy drinks and SQUIRREL! SORRY, I'm back , great video, I just screengrabbed so I xan argue with myself tomoro installing 4 relays for low+high speeds/dual fan..until it turns into something else and I end up moving my seat bracket 1/4"+ running out of daylight instead
Hi, what would make my 30amp fused fan cooling relay to get extremely hot? but fan still working,my fan stopped working i found out it was down to burnt out relay so i got exactly same looking replacement relay from Amazon with 30amp fuse (probably made out of chinesium),it melted the fuse cover today but didn't made it pop,fan must have been running for few minutes while sitting in traffic so pulled over and disconnected it so it doesn't catch fire waited for it to cool down and drove it back home with eyes on the temp gauge and heater fans on max🤦♂️(none of the wires felt hot just relay) thanks
This could be a really complex question to answer based on a variety of factors. First off, what is the amperage draw on your fan? If it pulls like 25 to 28 amps, then that could cause the relay to get hot.
The biggest thing I can think of that is overheating everything, is the wiring. What gauge wire are you running?
How do you have battery voltage source feeding the relay? You should at least a 12 gauge wire coming from the actual battery or at least a great high amp source. It is also highly important that your ground wire to the fan is at least a 12 gauge and connected to an excellent ground source.
How is the speed of the fan controlled? Does it run on one speed or does the temp sensor control the speed on how hot the temperature is?
There is no speed control on fans, they are either on or off. The temperature sensor is really just a switch. When the sensor gets to the set temperature, let's say 190°, it turns the fans on, when the sensor gets cooled down, it turns the fan off.
@RodsshopOrg ok so my next question would you recommend higher Watts fans if it's not keeping my truck cool enough. Currently have 12v 90w dual fan but just getting on the freeway they don't stay as cool & after a while with the AC on it starts to overheat if the truck is stationary but on the go not really.
@@hase1357 I am guessing you have two fans since you said FANS. It isn't so much buying higher wattage fans, you need higher CFMs and there is a difference.
I am helping someone right now on a Porsche that have super high wattage fans that requires a 70 amp fuse and blowing fuses and heating up wires. There is no point is jumping up wattage. Look at the CFMs and the wattage.
A good fan will pull lesser wattage and deliver the proper CFMs.
I know this may be a stupid question but need to address this first. Are you sure the fans are blowing the correct direction? Believe me, I have seen it all with electric fans.
If the fans are on the engine side of the radiator, they need to be pulling in the air. If they are on the grille side of the radiator, they need to be blowing toward the motor.
How big are the fans, as in what diameter? In all honesty, if the radiator is clean and flowing good, the thermostat is working correctly and is at the right temperature and the fan coolant temp sensor is turning on and off at the right temperature, most any fan is going to work.
The only times I have seen where a fan isn't keeping an engine cool standing still, is if it is really too small in diameter or a real low CFM fan. If your fans are pulling somewhere between 1200 and 1300 CFMs, it should work.
Get me the full specs on the fan. Go to my website and contact me through it so I you can email me some pictures of your setup and I am sure I can help you.
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@@hase1357 you can control the fan speed with pwm the Ford Taurus and fusions are the easiest cars to get a pulse width modulated box aka pwm in short it cuts the ground on and off on and off for a pulse which controls speed but the Ford have them on them that way for a dual setup you can have both fans on but lower speeds and then both on for high
Which sensor currently on the truck do you have to remove in order to use the sensor switch that comes with fan? The temp or sending unit?
They both have 5v signal, the new sensor is to be grounded so they can't go together right?
You need to be more specific, are you putting an electric fan on a vehicle that already has one? If not, there is no sensor to remove, you are adding one. Any other temp sensor that is already on the vehicle is for a light on the dash or gauge and you do not remove those. Please contact me through my site and explain in detail and send me pictures of what you are doing.
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How much Current require for that and can you suggest 12V adapter and what current require?
I am not sure what you are asking. Relays are measure in amps, so if you have a fan or component that you know is going to draw 22 amps, it would be safe to get a relay that can handle up to at least 30 amps.
If you need help on this, you will need to give me more information on what you are trying to do.
Really wish you could have showed a real hook up step by step, I get 30 goes to the battery and 87 goes to fans positive wire, the other 2 85 and 86 im so confused on, and where does the ground for the temp switch in the radiator connect to? I have it connected to the cross bar over the grill, and what about the black wire from the fan? Too many things I need visuals of to get this to work.
These instructions are pretty clear but also depends on what you are working on and your situation may be different. Contact me through my website, that way you can send me pictures and I can help you get what you are doing setup, I am here to help.
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@@RodsshopOrg oh I hooked everything up right just as you said, and it still dont work so idk anymore its ridiculous. 30 goes to circuit breaker, 2 bolt mechanism basically, connects to aux side then a wire runs from the stud labeled bat to the battery so that should feed a continuous power feed from the battery, the switch is just a substitute for in line fuse from what i understand. 87 ran to the power wire on the fan, 85 and 86 ones running to the temp sensor that's in a housing that is installed on my upper radiator hose, I have a ground wire running from it to my engine block and then the other I have connected directly to the positive side of the battery instead of an ignition power cuz it really don't matter as long as there is power from what I saw on other videos, my car is not going to exceed 210F just sitting in my drive way. So I don't know what else to do, I tried a different relay just to make sure it wasn't bad still don't work, monitored the engine coolant through my obd2 and it just climbs past 210 and nothing happens. Lot of vids say it dont matter which you use for each on 85 or 86 because it's DC and just a means to complete a circuit. Can you see anything I may have wrong there? I'll see what I can figure out on your website tomorrow I'm beat, and done messing with it for today. Just too frustrated right now.
@@bentramell729 This would be easier to help you through emails as I could send you a diagram to simplify this but from what you have wrote, I think the issue is your 85 and 86. All these two pins do is energize the relay, so as you found out, it doesn't matter which one is positive or negative but from what I read you wrote, and maybe I misunderstood it. But it sound like you have your temperature sensor trying to switch 85 and 86 together and that would be wrong. You need to add power lets say to 86. I usually make this a wire that only has power when the ignition switch is in the on position. Then 85 would go to your temp sensor. The temp sensor has to be grounded, so if you have it in a housing inline with the radiator hose, you have to run a ground wire off the housing to the engine block or some good ground. When the sensor gets to the designated temperature, it then grounds the wire that goes to 85 and energizes the relay which then sends power through 87 to the fan.
Please, if this doesn't work or make sense, contact me through my site, I am not going to use your email to spam you, it is just email makes sending pictures back and forth so much easier.
@@RodsshopOrg no it makes sense it's what I've done, I have 1 of the wires, 85 or 86, not sure which but one of them is running to the temp sensor in the housing inlayed in the upper radiator hose, the other one is running to the positive post on my battery. I have a ground running from the temp sensor housing to the engine block. 87 running to my fans positive wire, fan is grounded. 30 runs to the circuit switch and then from the circuit switch to the positive on the battery. It should work I don't understand why it dont. I've tried two different temp sensors and 2 different relays and still nothing. I don't think my problem lies with not being hooked up right but rather or not my wires have proper connection or maybe my radiator fluid was too low not really reaching the temp sensor inside the hose and just passing under it. It's a head scratcher though. I won't bother you anymore, I appreciate you talking this out with me but im certain I have the schematic of it hooked up correctly there's just something else that's not right, idk maybe my ground from the housing to my engine block isn't in the right place, I did have it on the crossbar over the radiator where the hood latch is at like I saw other videos with this same set up put theirs and it worked just fine on theirs that way and didn't have to be on the engine itself. Maybe my circuit breaker is bad and not translating power like it should on 30. Lots of variables that are going to be difficult to test.
@@bentramell729 Before you give up, go back to the basics. First off, you may want to watch my other video on relays: th-cam.com/video/5wVeCYuDJuI/w-d-xo.html
Going back to basics means, ignore all the switches and sensors and just run wires to the relay to see if you can trigger it. I have another video where I put electric fans in a truck. Here you can see how I just ground the wire going to the sensor to trigger the fans to kick on.
th-cam.com/video/W5Ucc63uvn4/w-d-xo.html
You can see me go around the sensor at time stamp 36:12
Contact me through my site, send me pics of your setup and I can get you going
Question, wired everything up and everything worked but I had relay chatter and the temp sensor melted? Problem?
Sounds like the sensor wasn't grounded good and created a current overload. Or you do not have it wired correctly. The power on the sensor is supposed to be low, all it does is turn the relay on and off. If you have the sensor switching the full amperage to the fans, this will melt everything. Are you sure you have it wired correctly? I ask because even if the sensor isn't getting a good enough ground, the current should be so low on it that the most could happen is it doesn't switch the relay. I can help but contact me through my website so you can send pics of what you did. rodsshop.org/contact/
Recently got an LS3 Swap. Exactly what I was afraid of happened. Shipped it to another state to the expert and now I’m having issues and we are trying to figure it out over the phone. Started with over heating. Found one of dual fans stop working because fuse melted inside its inline wire case. Fans are wired to be on as soon as I turn key to on. So I replaced inline fuse wire and 40Amp fuse. Now after 10 minutes of fan running relay so hot you can barely touch it. So I swapped the relays and the one getting hot didn’t get hot anymore but the new one on the side with fan issues did.
The installer is sending me a new relay, he says the base the relay connects to can be bad, but I just don’t see how. But everything is possible. Today when I get home I’m measuring the resistance of each fan. Hopefully I don’t have to cut any wires to do this. Any advice?
This is probably a bit much to try and discuss in this comment section, so talking through my site might be better. rodsshop.org/contact/
It sounds like you have a bad fan more than anything. You need to measure the amp draw, (the current) for the fan in question. I would run jumper leads off the battery to run the fans outside of the fused and relayed wiring. Use a volt ohm meter that can test amps and run it in between each fan. I would measure the amps on the fan that you know is working fine first. That will give you how many amps it should be drawing. Then test the fan in question.
Be sure to check the ground on the fan in question. A bad ground will cause it to pull more amps but no fan unless it is huge should be pulling more than 20 amps. So if you had to run a 40 amps, you are just waiting for a fire. Check the current draw before going any further. Contact me through my site and let me know what it all said and I will try and help you through the rest.
If I have a trunk mounted battery do I need to run the power wire all the way to the trunk or could it go to a constant power source in the engine bay somewhere like the starter relay?
There should be a junction under the hood where you can hook jumper cables to if you ever need a jump start. Look for it and you can just run power off of that.
@@RodsshopOrg it’s a 71 cuda so the only positive under the hood is the starter relay or the actual starter stud the battery cable connects to.
Then yes, just come off that terminal for your main fan power and that should work just fine. Just be sure to use the appropriate gauge wire for the amp draw of your fan. I would run no less than 12 gauge if this is a more common fan that doesn't pull more than 15 to 20 amps when it first starts running.
@@RodsshopOrg thank you for the help
What type of 40amp relay to buy, normally open or normally closed there are a few types out there, cheers
Any regular 4 PIN relay is always open. This is shown in the video, PINS 30 and 87 are open until you add low current to PINS 85 and 86. This is going to be the same on all amperage rated relays.
What is the single prog thermostats ground? I have it on a inline lower radiator hose dose it still need a ground?
I am not sure what a prog is. If you are talking about that housing that the temp sensor goes into, it does have a ground wire to the housing and it can be run to the engine block. If am answering that wrong, let me know and I will do my best to help you.
I hooked up my fan to a led light bar harness, and it’s not spinning as fast as it was hooked up directly to the battery, the relay is a 40a and fuse is 30a, what can I do to get the fan to spin faster?
You need to go to a heavier wire. LED lights are low amp wire, the fans need at minimum a 14 gauge wire, I prefer 12 gauge. More than likely, the LED Bar wires are 16 or 18 gauge wire and that isn't heavy enough to run fans. @josebuenrostro9080
Thanks for replying 👍 so just replace all the wiring with 12 gauge? They are 16 gauge wire after the fan connector
Yes, 12 gauge would be best. Also ensure that all your wire connections are good, as a bad crimp or connector not making good connection can also cause your fans to run slower. @@josebuenrostro9080
@@RodsshopOrg I put 10 gauge and everything is looking good but when I flip the switch it feels like my truck is gonna die from the current draw but it picks back up since I upgraded my alternator, would you suggest I get a new battery as well?
How old is the battery and what cranking amps is it? If you beefed up the alternator, that should be enough. Just how many amps does your fan pull and how many fans do you have? @@josebuenrostro9080
Where do you hook the ground wire to fan motor
Run the ground wire to the radiator support or even to the negative battery cable. Just ensure that it is metal that is fully grounded. You can use a multimeter to check ohms between the negative battery post and what ever you are going to ground your fan to. Just make sure there is no resistance, if not sure, run a wire off the negative battery post to the radiator support to ensure it is grounded.
Thank you thank you 🙏
Glad I could help
hello there I have a 1999 Isuzu order, I need to wire a trans cooling fan, I want it to come on when I start the car and stay on untell I turn the car off. what can I wire pin 85 to so that it will have power when I start the car?
You just need an ignition wire, check for any wire that becomes hot when you turn the key on. I do not remember on your vehicle off the top of my head if it has a coil pack or some form of an ignition control box, but any wire to these type of devices you can use to trigger your relay. If you need help, you can always contact me through my website and I will do my best to guide you. rodsshop.org/contact/
@@RodsshopOrg yes each plug has its own coil pack-should I look for a wire coming out of the fuse box under the hood?
@@williamtreat5893 Yes, if you can find a fuse that gets 12 volts only when the ignition key is on, then you can tap off that. You can also tap off the alternator, not the main wire that charges the battery but the one that engages the alternator. You will need a volt meter or test light but either should supply you the voltage you need whenever the ignition key is on.
@@RodsshopOrg first let me tell you that I'm wiring a trans cooler temp sensor and it will be going inline between two rubber hoses-the temp sensor has two pins sticking out of it, so I wire one of them to pin 85 - that's the wire that has power only when the car is running right? so when the temp sensor reaches the temp it will send power to pin 87 and tell the fan to turn on right? do I wire the other pin from the temp sensor to pin 86-for a ground? you did say at the start of the video that pin 86 could be used as a ground or do I need to wire it somewhere ells? and NOT to a ground- the little metal bracket on the back of the relay where you mount it to the firewall is that not a grounding point? i just don't know where to wire the second pin from the sensor-you would think that if one pin was hot and the other pin was a ground when it activated the hot and ground wires would be an electrical problem
How about running relays from fan controller
I am not clear what you mean fan controller. Are you talking about the switch on the dash or are you talking a control that can vary the speed of the fan. Please clarify...Thanks
@@RodsshopOrg I'm sorry I have a flex a lite fan controller on 2 derale 12 inch fans and I wanted to run some relays to reduce the load I have them on the controller and one 50 amp fuse and the fuse gets hot
How do I put a temp gauge in a single set up
If you are wanting to hook up a temp gauge off the sensor that triggers the fan, it won't work. The sensor that triggers the fan is basically a switch and will not operate a temp gauge. You will need to find another port in a head or block or even the radiator to screw a sensor designed to run a gauge. I am not sure if this answers your question if not, let me know if I have misunderstood.
How many amp your relay?
30 amp but for you, it is going to depend on what you are running. You need to check the amperage draw on your fans or whatever device you are going to be running. But in most cases, a 30 amp breaker should be enough to run cooling fans.
Thank you for taking the time to make this video. Very informative, it was very simple and understandable
Glad I could help.
I installed a dual fan in my 86 c10. Installation was painless. The issue I have is once the temp rises and the fans kick on they don't kick off. Could this possibly be a bad relay? Thanks in advance
It could possibly be that your temp sensor for the fans is a less temperature than your thermostat. In other words, if your thermostat is a 190 degree and your sensor for the fans is 160 degrees, the water temp is never going to get below 160 to shut off. I am guessing the fans turn off after the engine cools off, you may need to give me more detail.
@@RodsshopOrg I utilized the temp sensor that came with the kit and installed a 160 thermostat as well. The only thing I did different from your wiring video is the key switch and the temp sensor are reversed. So at the moment the white wire is tied into a key switch source and the black wire is tied into the temp sensor sending unit. Due to following another how to video.
Damn it, I just went to auto zone and they gave me a 5 pin relay
Why not just use a 20 amp switch to power fan, you don't need the relay.
Well maybe most people are not as diligent as you to remember to turn on the fan when the engine starts to get hot. Most people do not want the fan to run all the time nor is there a need for the fan to run all the time. We are in the 21st century, so most people want things to be automatic. But if you are happy just turning on a switch and remembering to turn it off, then I say go for it. This video is if those that want to hook up a relay for any item if you want to, not that you have to.
I have 1998 Oldsmobile cutlass GLS 3.1 my fans will engage if I turn the AC on. I changed fan relays fans are not turning on by their self when just idling at a red light it will go over half and start to overheat. Replace water pump thermostat and flush. I’m still overheating If I sit at a red light too long?
Sounds like the temperature sensor isn't working, there is ways to test that. Contact me through my website so I can help you. It is just too hard to communicate through TH-cam comments, we may need to share images. I am not going to spam you.
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