I have a 2008 Mercedes S550 at my shop with a wheel speed sensor code. After checking a known good wheel, I found myself confused when I didn't see any square wave. Then I remembered watching this video over a year ago. After re-watching this video, my mind is refreshed. Thank you Paul!
I had actually run into this design on a 2005 dodge caravan today. I checked the first "feed"wire and found the 10.8 volts. Then moved to the other wire which read 0 volts. I expected there to be a change on my scope when I spun the wheel on a known good sensor. Nothing. Then switched back to the "feed" wire and spun the wheel and saw the very slight change. Verified on one other wheel and found the same. I know if it wasnt for your videos, I would be at a complete loss for any understanding of diagnosing such issues. I really appreciate all the hard work you put into teaching us all.
The obvious point of the video/lecture/case study, Do your homework. The very moment my uncle informed me that we would start letting me diagnose vehicle problems, I went out and purchased a laptop just for doing my homework, which yes, is the responsibility of all technicians. I often have to revisited theories and operation and adapted them differently depending on make/model/year. I think being on a computer at work also explains my tunnel vision at times, lol. Awesome video Paul
Thank you for another great lecture of the diagnosis process. Now I have a much clear idea of this type of circuit. Recently I got a code of front right wheel abs sensor of a 2010 Jeep Compass with the system described by you on this video. First I thought it was a 2 cables VRS and this is what I did: -Measure resistance: both front wheels O.L. - right back wheel (for reference and because easy acces) around 27 Megaohms. -AC voltage left front sensor and while spinning the wheel: unplugged 0 (V), connected and back probed 100 mV (I didn´t pay attention then but I think this voltage remained the same regardless the wheel speed, but I´m not sure). -DC voltage: 11 (V) supply - 0.05 (V) ground (I measured DC just because a saw a + and - on the sensor connector), a variation in the supply of about 400 mV while spinning the wheel. I found it has 2 states like HALL sensor. If you move the wheel very slow to catch the hump it will make the change of 400mV. I couldn´t see the teeth or humps in the sensor hole or by any angle. -The front right sensor did nothing, pins and the harness side were good. Hope this will help someone or just for the discussion and of course I would very much appreciate your opinion Paul.
Nice to watch who's giving good explain, not like many other useless mechanics who can replace without any investigation... And can't explain where problem was... Good job😊
I'm a hobbyist. But I have bought my Autel Maxisys, and are getting me an oscilloscope. This is the second video I watch from you, and I can see that I will learn alot from your channel. Thanks
Thank you very much for the lesson. I change the steering knuckle an a Audi A6 C6 and become a failure on ABS Sensor. New Sensor without success. Trying to test the Sensor out of the car was, with the description from Hella not possible. Thanks to your video it works. 8-9 Volt on supply with a 450 ohm resistor in series and AC coupled Scope direct on the Sensor works fine. Presence Signal with 1.43 Hz and clean rectangular signal o Spinn . You save my day!
Hi Paul, I've worked on 2011 Volvo XC60 today and I've used well instructions from this video:) great job sir, I've also tried bypass test on supply wire and you were right it is pull down design- I could clearly see wheel speed change by tapping back probed supply wire with incandescent test light - surprisingly it wouldn't do that with LED test light. Unfortunately I couldn't really see 400 mV voltage change as I've only have Fluke 123 scope meter even using A/C coupling - I've seen some fluctuations anyway:) These Volvos are using one different wheel speed sensors on RHF wheel ( white colour) then the rest of the wheels (black coloured sensors ) reason for that is that RHF sensor is used to measure wheel rotation direction for correct operation of CITY SAFETY SYSTEM. Great video again Paul - thanks man. Cheers.
Paul this is one of you're very best video it is informative educational and entertaining I love your style when dealing with the inaccurate flowchart very thoughtful I could see you carving out a career as an expert witness in legal cases about anything to do with the automotive industry thank you so much for this and everything you do cheers
Excellent explanation mate, I have a 2013 Navara D40 STX550, I wasn't able find any faults in my abs sensors using all other test methods including some flow charts. It was looking like a very expensive fix, with Nissan explaining that all abs sensors need to be replaced starting from the very expensive front ones and eliminating from there. Luckily I found your master class on this issue and its exactly the same scenario we were following. Using your method, we uncovered that the newer d40 Navara/Frontier uses the same 7mA-14mA range as the car you were testing. We found only the rear LH sensor to be faulty and read 0mA, a much cheaper fix Thankyou very much for posting this.
Just ran into this type of ABS magneto resistive ABS circuit on a 2007 Gran Caravan 3.3L. Scanner shows ABS fault codes for missing input signals to all 4 wheels, the RF is obvious, the ABS wire came loose from its mooring point (rusted off bolt attaching to strut) and got damaged. On LF, I backprobed and found the almost battery voltage on one and zero on the other, spun the wheel, nothing changed on either. The back sensors had the small ripple voltage riding on the 10.6 volt supply wire, so not sure why they triggered the no input from those sensors. Currently waiting on delivery of the replacement ABS sensors for the front, will update once they are installed and codes are cleared. Thanks Paul for the video, for conventional testing with alldata repair info would have led me down the garden path for sure!
Meant to mention in my post..since you cannot rely of repair info for accurate information on this type of ABS system, how are you really able to figure out what you are dealing with, if you were not fortunate enough to watch this video? You would be going against all conventional 'wisdom' if you didn't believe what Mitchell and Alldata were telling you.
Hi...I believe the signal is usually represented by change in voltage. The ground wire voltage is constant throughout the process, means that the only voltage change we had here is the wire which has the 10.5 v. That is why I agree that the supply voltage is the supply and signal wire.
great video Dan It show how things are in electronics in general, when you look at a circuit at first, its not what it seems, the problems with incorrect manufacture data is rampant, even in the tv trade. many a day was lost looking in the wrong direction, on the plus side of electronics, you are forever learning
No, not at all Paul, if anything you deserve praise by no only myself, but your other viewers and your students. I would like to see more starting system variables. I don't want someone to do the bypass test, their vehicle cranks but does not start and they think there is another problem(you either make a left turn in your diagnoses or a right turn) and system variables are going to help dictate that. That is all and oh man, anti-theft(gm's passlock notorious for issues) that would make a great
You're right, I think the better way to reach a decisive conclusion is to do further testing. May be it is time to short the sensor ground with another signal ground and find out if the computer will set a DTC for the WSS. If the ABS module sets a DTC then the sensor ground is the signal wire.
On some of the Chrysler vehicles(this refers back to your older Dodge neon starting system video/lecture, the key DOES NOT have to be on in order for the ign. switch bypass test to work. This is because the computer does not directly control(supply a ground) for the starter relay coil(the reverse light/neutral safety switch, all one assembly) grounds the relay coil as long as the vehicle is in Park or Neutral. In that case, the vehicle, will just crank over(the pcm is not alive, thus the ASD and
Hi Paul well I think you done the right thing in testing the circuit explained what done what etc, you cured the problem with a new sensor, think it's a case of what have you got and how does it work and what does what...Fred uk.
I think you guys are on the right track the ground wire is signal wire that's why the schematic labeled ground as signal. If feed wire was the side CAB was using for reading speed signal you could use external ground I think. My bet is that ground is the signal.
I believe the CAB detects changes in CURRENT on the signal wire, I would think if you have 12 volts on one wire and a ground on the other and there is a small current square wave on both wires the system is working correctly Fred UK.
I had the same issue acquiring a clear scope signal on an ABS speed sensor on a late model Jaguar X-Type after seeing no left front speed signal on the data list. I had to AC couple the signal so I could set my volts per division down to a level that would show the digital signal. Very low voltage switch on a good sensor (right front). The left front hub bearing was in backwards (internal reluctor).
wow, thanks this was just what I was looking for. Replaced rear wheel hub on my dodge journey and it came with an another type of abs sensor than the original. Luckily the connector was a little different, can't imagine whatever could have happened. Used the old one instead. Greetings from Finland 😊
great video. wouldn't their also be a small sqaurewave on the 06 Colorado supply wire since its between the module resistor and the changing resistors in the sensor?
great info! I know I'm late but you can measure mA with your scope by looping a jumper wire for your clamp, each loop after the first is X=1 i.e . with a loop of 10 your reading X10 so a 1 mA sig would show as 1A , 20 loops = 2A. this will allow the scope to actually "show you" whats happening'. This is something I learned with my fluke amp clamp in the late 80's. And should be the best way to read the newer WSS without the drama.Simply add jumpers between WSS and EBCM with extra wire to allow for your X loops set DSO to approx range and spin away.
hi, do you mean Oxygen sensor by the air/ fuel sensor? if you mean that, then Oxygen sensor monitors voltage (not current) from 800mv at rich and 200mv or less at lean. I think if the computer ground (sensor ground) is shorted with other ground (body ground) we may have a DTC of signal short ground, in case we have a difference between the two ground.
Not at all! I was thinking the same thing while editing this video. "man I wish I would have grounded that ground wire to see the response. Next one I get you can be sure I will do that. Thanks!
The 2008 Caravan uses a Hall effect ABS wheel sensor, it has internal electronics, you will see an open circuit testing it with an ohm meter. You will see 11 -12 volts DC if you measure between the 2 wires when sensor is connected to vehicle and ignition set to on. Leave meter connected across wires as before with ignition on, set digital meter to frequency mode, now rotate wheel and watch for frequency reading, on good sensor I see 40 - 50 Hz turning wheel by hand.
I would think if there is a voltage square wave on the positive wire it is being caused by interuptions in current by the sensor.prob. causing a voltage drop on and off, a good way to test it...Fred.
Hi Paul a bit heavy going that one, will have to watch it again, bit confused, what do you have on the feed wire without the wheel turning, just 10.5 volts dc or a square wave, if its a square wave is it origanally generated by the computer, can see what the sensor actually does, does it modify the square wave, so the one coming in is different than the one going out when wheel is spinning, have to watch it again, very interesting though....Fred UK.
As you know that pin 4 in DLC represents body ground and pin 5 represents signal ground. So I think there is a difference between the two grounds that can be detected by the computer.
Hi Paul I think I see, you have a 12 volt supply to one wire with a square wave on it coming from the computer, it goes to the sensor and comes out modified relative to wheel speed which goes back to the computer on the earth lead...the square wave should stay the same on the supply lead if wheel is turning or not?? unless it is effected by current flow?...Fred UK.
no problem man thank you. emotions are lacking in this form of communication and I suck at it sometimes. I apologize as well if my questions in return seemed harsh. It was not my intent. Have a great evening my friend.
ive read that your suppose to use a micro current probe, which is also how you test wideband o2s, problem is no body sells them yet and if they do its over $700 Paul idk if your verus is more up to date then your vantage pros but if it is ... cant you look at component tests on it to see if they changed the info? i noticed your vantage is 11.4 mine is 8.4 .
Had 03 Lesabre air bag front end crash sensor code, it used a digital current signal milliamps. used very low current clamp & picked up digital signal on bad & good sensor with initial turning key on. Since these two sensors appear to function almost the same other than one has reluctor wheel and other must have an internal moving part. I am now wondering if I could have also used the ac mode without a current clamp too at least view the signal with a lower scale on a scope or graphing meter?
The circuit in this sensor is very similar to a three wire only difference is instead of open collector output, the output is a current source of 7mA being switched on and off. The circuit always draws 7mA mostly to power the hall cells. Typically a 100 ohm resistor is used to sense the change current which is in the CAB. This resistor can be on the ground side or the high side of the sensor. It doesn't matter.
I am in alignment with many of the comments below in that this circuit is very similar to the air/fuel sensor circuit. So far, I only know how to debug an a/f sensors by using the scan tool, snapping the throttle, and looking for a characteristic wave form on the a/f pid. Well, that works when the sensor and circuit works, but what the heck do you do when that test fails... Pain enters the ball game. I'm still in the process of researching ways to debug this type of circuit. What concerns me is that it appears the manufactures are slowly turning to this type of circuit. I'm guessing it might save on internal circuitry costs in the controllers. Again, thanks for all of your time involved to share your knowledge and findings.
I just ran into this on a 2012 jeep liberty but get ground on both wires on the harness side. I checked for open wires and shorted wires but they are intact and not shorted. I back probed the pin at abs module with sensor unplugged and still see ground. I suspect bad module. Is there something I missed?
Paul Kinda curious. Could you of checked a good known sensor and that bad for resistance. Great video. I understand fully. Buy the way. I took your advice at bought a used vantage. Great front door tool. Maybe when I grow up I'll upgrade to the vantage pro
Fuck me 😮 almost fell of my seat. 10 Years makes a big difference. Watched all his new stuff and then this popped up😅. He's definitely gotten better with age 😊
Okay cool, I understand now. I was okay with the suggestion either way, just wanted to make sure I understood where you wanted me to go. Thanks jarin, I will add it to the list :)
awesome video, im your fan from PERU, i had a problem with a 2008 hyundai tucson 2.0 with no activity from the O2 sensor 1 code, the computer only read the bias voltage all the time, but the weirdess thing was that the pcm was in close loop and my short and long term was in -35% in every engine speed, when it was in open loop the engine was running well, but in close loop the pcm took all the fuel away, i dont understand why it did that?
I have some confusion that I'm hoping you can clear up. I am working on a VW that has the same type of WSS as the jeep discussed in the video. It has WSS codes for both rears and scan data shows 0mph at all times. Both sensors produce a signal exactly like this jeep when spinning the wheels and looking at a scope. My question is, if the sensors are producing a signal, does that mean the ABS module is faulty?
@ScannerDanner I did compare to the fronts and found the same thing, a small square wave on the supply circuit exactly like the jeep in the video. I was also confused at first because the "signal" circuit is just a ground, but the description of operation did state that there is no separate signal wire and that the signal is superimposed onto both signal wires. Could it be that it uses current as the signal instead of voltage?
@ScannerDanner Sorry, I should've been more thorough in my initial comment. I hooked up the scope at the module as well and the signal is still there. I hook it up to the supply circuit and see a square wave that ranges between 10-11 volts.
Thank you for the informative video sir Paul....the idea is very great.,can I asked something sir? Because as I watching this video what comes up my mind is this...for example if we haved a bad wss on a front RH, can we simply disconnect both connectors of front wheel wss, and put a two test probe on a good one wss then connect a patch cord from it and ran that to harness side of the bad wss with already two test probe also connected then spun the hub monitoring wss parameter to react? To tell circuit and module is good?..then conclude sensor problem? Only used the known good side sensor to get information if my circuit and module is good?.....I keep watching your videos sir to build knowledge,strategies,how to approached concerns....thank you god bless sir Paul
+Robert Lesaca yes, sometimes :) the oscillation can actually be from a voltage drop from current flow in some situations. (not so much here with this very low current circuit)
Hi Paul I have watched it about 4 times, I think we have come to same conclusion, the CAB supplies 12 volts to sensor and the other lead goes to ground, when you turn the wheel I believe the sensor chops the current up, and you get a small square wave of current on both wires, the voltage wave just caused by a a voltage drop due to current change...how's that, so technically earth wire is prob signal wire - Fred in England.
commenting about the signal wire as identified by the wiring diagrams. could it be that the module is monitoring current flow instead of voltage and they are doing this on THIS wire so they call it the signal wire.
Thanks for the video as always excellent. I am sorry but I am not convinced that the ground side is not also interpreting the amperage change as a signal at the CAB so if there was a short to ground on that side we could have a bad interpretation at the CAB. I am thinking I'd test wave across sensor using the circuit ground as ground and if there is a varying voltage I'd do normal short to ground tests. Possibilities include the possibility that the circuit is broken and shorted to ground. Any thoughts? Am I missing something? Thanks much again for all you do!
you could be right. we will need to do some further testing on the next one for sure. and I already planned on it. I am going to short the ground wire to ground and see what happens.
ScannerDanner my Hantek scope does not support ac coupling, I have not encountered this type of system yet, but do you think if I were to connect the ground lead of my scope to BAT pos instead of ground, could I pickup the signal because the system voltage would be steady and the sensor voltage fluctuates. Therefore the scope would measure the difference in voltage, giving a display of a signal waveform?
+Joe Nause I have Hantek as well, and it having only DC coupling is fine, all AC coupling is for is to filter out the DC component of a waveform. DC will pass both types of signal.
Aware of that, but to get more detail on the signal riding on top of a dc signal, you need ac coupling. That is why I went to bat positive and the signal wire. other wise i would only get a 12v line with a very tiny 50mv ripple on the top. Reducing the scale drives the waveform off the screen, but reducing the scale and ac coupling puts the waveform right on the zero line
Far as I can tell, you really only need to see that small ripple voltage for the most part to tell you there is a signal there. I just went through it with my Hantek. Would be nice to zoom in, but really just need to know the signal is there.
Yes, this works very good with the Hantek without AC coupling. The next time i have to work on such system I will try with a condensator ( ? mict farad) in serie.
Morning Paul, at this rate I can see you doing a follow up video to this one, seems to be a lot of controversy, good luck on that if you do, I think maybe a short to ground on the so called signal wire might be an idea on what to do...Fred.
What do you call INTELLECTUAL AND PRODIGY and SUBSTANTIAL add one more ACCOMPLISHED the answer is Sir ScannerDanner My teacher Start to finish tutorial great thank you loved it Take care and have a great Evening with all your family around you PROFICIENT Sir ScannerDanner From Nick Ayivor from London England UK 🇬🇧
If the wheel sensor is bad, and I go to live data for abs system on a professional scanner, will the bad sensor be showing speed for that wheel? Shouldn't one of the wheels be staying at zero mph when the car is moving if a wheel sensor is bad?
Thanks...So if all the wheel sensors are showing the same speed, and changing speed with the cars speed, then it can't be a wheel sensor that is keeping the ABS trouble light on? Most likely the ABS module? Brake fluid is full, and all brake pads are at 90%
Here is the whole story: I am working on a 2003 Lincoln LS V8. I have the ABS light on..Scan tool shows DTC in ABS as C1998 which is re-calibration of ABS. Is there a way that I can do this my self without taking it to a dealer or shop? All wheel sensors are working properly according to live data on scanner. I think this is due to dropping the steering assembly to the floor for a while when removing the dash for AC evap core replacement. I have an Autel MaxiCOM MK808 ..No bi-directional control, but does about everything else..I just wanted to make sure that the wheel sensors could not still be the problem. I also have Forscan on my computer, so it may be possible to do it through there if the Autel will not. The SRS light is on also, so it may be possible that the clock spring ribbon cable was damaged from the steering assembly being dropped...which may be messing up the steering angle sensor too?...thanks
Hi I agree it is usually by voltage but this is an abnormal circuit, it's a wonder it works at all, but basic law of electronics states the current is the same throughout the whole circuit, it always is...FHS.
Hi Ali, well that might be the way to go, bit of a funny one to say the least, makes you wonder who designed the system, I thought the reluctor teeth looked a bit small...have a good day, Fred in England.
Good video, every time I watch one of you videos I learn something thank you excuse me do you know if one of this WSS can power the ESP, BRAKE AND BAS light cause I got a 2007 chrysler 300 with those lights on right now and I dont know if it's the WSS or ABS module thank you in advance
step 1 is to scan it for codes my friend. Typically the red brake light will not be illuminated from a speed sensor issue. The ESP light will though as it is part of the same system. So anytime your ABS light is on, the ESP light will be also. But the red brake light is typically something hydraulic that has failed
@@ScannerDanner Hello Paul this is the code C2206 Chrysler ABS Vehicle Configuration Mismatch, I dont really know what this mean but in some videos said the ABS MODULE I dont know if you work in some of this cases and probably can help to me to figure out thank you in advance and have a good day
Let's move this to my forum. It is free to join and is definitely easier for me to help you there as i have paid moderators who are there to help me help you guys. www.scannerdanner.com
let me start by saying thank you. your videos are awesome and I learn more and more from you every day.. can I be so bold and ask you a question and what direction you would go.. I'm working on a 96 cat Fleetwood and the ABS and TRACTION light goes off and on...at stand still the MPH all the wheel speed sensors are reading all over the scale. 1- 80 mph at a complete stop... also system voltage the ABS is reading is all over the scale..zero thru as high as 15volts... when the scan tool see voltage I noticed the pump motor turns off and on as the voltage appears and disappears.. I'm a little lost and irritated I cant find a problem.. lack of experience and understanding on ABS I guess.. I have video and schematics. id love to send them to you and my findings.. customer is just going to have to wait.. and I hate getting my ass kick lol oh, vehicle system voltage is good all the time..its just the abs module is seeing an erratic voltage signal...thank you, I know your busy... I would appreciate your input
No V on signal wire while 7-14mA on the same wire tells us that there is no resistanse in a CAB on that wire and all the voltage drops at sensor. So, you better dont put 12V on that wire to test it....something in CAB might burn. Am i right?
Paul, I have a request, but I would like to message you personally. Your class would benefit from my suggestion and of course you would enjoy lecturing on it. It also involves a case study so that would be cool as well. Thank you for your time.
Wow, amazing video sir! Chrysler screwed up REALLY badly on that service information. A typo or a miscopied wiring diagram, I could understand... not blatantly wrong information. My personal go-to test for single WSS codes involves jumper wiring a working sensor into the harness for a suspected bad sensor, and watch scan data for a response. Is there any reason that wouldn't work with this design of sensor? Also, enjoying the new format!
Hey Paul I was wondering how do you use Mitchell wire diagrams I'm very interested and in how to do your class on line if you do it online and if you give a certificate and end of training ? PLEASE. READ. .. . . .!!!!!! 😃
Fuel Pump Relay are not energized. My suggestion is this, two vehicles with completely different starting systems. You do your ign. switch bypass test on both, explain what you are doing and why one starts and the other does not. The point being, yes the bypass test is awesome and critical at times, but you are only talking about jumping one wire and that not all systems are active doing that. Those differences in circuit design are imperative to know.
So what you are asking me to do is to cover the workings of the ignition switch? And to do it on different systems? There are so many variations. Run circuits, crank circuits, anti-theft involvement, accessory circuits. Computer controlled, non computer controlled, push button systems...... The bypass test I did was to prove the ignition switch was bad on that one system. It wasn't a test that can be done on everything and I do not believe that I led people to believe that. Did I?
just went through this today. spent a couple hours trying to figure out why the known good wheel was not producing a signal, but in the scantool showing speed. here i am at home trying to figure out why my labscope was not producing a signal. going by alldata and outside information, now finding out wrong information. !!!
i can hear vince fischelli screaming to put a batt. pack in parallel to keep base system e good and charged, only after of course after you clean the batt terminals and check batt. ground E drops if any
Had to work on a Pt cruiser yesterday earnt my $99 AU quickly because I watched this video ages ago and remembered ! Ac couple low voltage scale Cha ching
Hi Scanner Danner, I have a VW Golf mk6 cayc with the same type of sensor Magneto resistive, I have identified it with the help of this video. My problem is I have battery voltage and signal on the same wire for both left/right wheel speed sensors but no ground feed to my Front Right speed sensor but i do for the Front Left. I did a continuety test from the right sensors ground pin to the abs module connector and continuety was ok. Which lead me to think it was a computer issue. The only evidence I have is that the car has had a rat infestation but cannot see any damage on the surface. I am getting various codes showing which are 01279(longitunidal acceleration sensor adaptation), 01435 (brake pressure sensor 1 adaptation), 00778(steering angle sensor adaptation), 01423(lateral acceleration sensor) But my main concerns are= 01314 (engine control module read trouble codes - intermittent), 00285/00283 (left/right wheel speed sensors G45 electrical problem intermittent), 00668 (supply voltage terminal 30 upper/lower limit reached - intermittent) and finally 01305(databus for infotainment - no signal/no communication) Is there any advice you can give me please? Just seems like a coincidence that it is the left/right front wheel speed sensors acting up and not the rear as they where the only sensors i was previously experimenting on trying out my new ocilloscope checking for signals lol.
Hey, post this to my forum 😉 www.scannerdanner.com/forum/post-your-repair-questions-here/3757.html You can reply here when it's up. I'll see it. My wife helps me with the support inbox, so we can leave her alone lol I just happened to be doing some this morning.
It really sucks when a manufacturer can't get their diagnostics/trouble charts correct - ultimately that means the customer pays for a bunch of extra labor for a tech to figure out how it really works, and probably for parts that weren't needed in the first place.
Great video once again. Ignorance is NOT bliss in this case! Why would manufactures wan't to standardize the digital wss.... (add sarcasm here) that would make it wayyyy to easy to diagnose...lol, Thanks for letting the 'cat out of the bag' Paul and letting us all know how wss work in different ways. Take care
Hello. I’m not sure if you bother monitoring comments on your videos from so long ago, but I feel compelled to comment. Also I’m not sure as to what you wished you would have done/tested but didn’t. It’s possible that is what I wish to comment on. As you did mention, it is/was possible for the ground wire to be the signal wire, but it appeared like you were somewhat ruling the out. You noted that you got the same amperage on both wires but no voltage was present on the ground wire. I believe that to be impossible. Had you adjusted your scanner to the 1 volt range as you had done earlier on the power side, you would have had to of seen the same mil-amp reading. Would you not ? It is my belief that what you believed to be the ground wire is/was in fact the signal wire. As it would/is far simpler to measure mil-amps at low voltage than to think you can get a reading off voltage drop from a voltage supply that is never 100% constant. I want to say I very much enjoyed your video and plan to subscribe. I’m hoping you have videos on testing just the sensor/pickup on various types. Thank you.
"You noted that you got the same amperage on both wires but no voltage was present on the ground wire. I believe that to be impossible. " This is a fundamental element of current flow. What enters a circuit, must leave a circuit. The exact same amount. So my point is, you can measure the power side or ground side of a circuit (no voltage on the ground) and read the exact same current flow. Did I also do a bypass test on this sensor? With a test light? I don't remember. IF I did and was able to trigger the circuit and cause the scan tool to show a wheel speed, then I absolutely identified the correct wire as the signal wire. I'm sorry though, it has been so long that I do not remember. Thanks!
Literally walk your students through two starting system wiring diagrams and trace the wire that you bypassed at the ign. switch and show them what it does and what it does NOT power up and all the variables involved.
I have a 2008 Mercedes S550 at my shop with a wheel speed sensor code. After checking a known good wheel, I found myself confused when I didn't see any square wave. Then I remembered watching this video over a year ago. After re-watching this video, my mind is refreshed. Thank you Paul!
I had actually run into this design on a 2005 dodge caravan today. I checked the first "feed"wire and found the 10.8 volts. Then moved to the other wire which read 0 volts. I expected there to be a change on my scope when I spun the wheel on a known good sensor. Nothing. Then switched back to the "feed" wire and spun the wheel and saw the very slight change. Verified on one other wheel and found the same. I know if it wasnt for your videos, I would be at a complete loss for any understanding of diagnosing such issues. I really appreciate all the hard work you put into teaching us all.
Thank you Justin!
The obvious point of the video/lecture/case study, Do your homework. The very moment my uncle informed me that we would start letting me diagnose vehicle problems, I went out and purchased a laptop just for doing my homework, which yes, is the responsibility of all technicians. I often have to revisited theories and operation and adapted them differently depending on make/model/year. I think being on a computer at work also explains my tunnel vision at times, lol. Awesome video Paul
Thank you for another great lecture of the diagnosis process. Now I have a much clear idea of this type of circuit. Recently I got a code of front right wheel abs sensor of a 2010 Jeep Compass with the system described by you on this video. First I thought it was a 2 cables VRS and this is what I did:
-Measure resistance: both front wheels O.L. - right back wheel (for reference and because easy acces) around 27 Megaohms.
-AC voltage left front sensor and while spinning the wheel: unplugged 0 (V), connected and back probed 100 mV (I didn´t pay attention then but I think this voltage remained the same regardless the wheel speed, but I´m not sure).
-DC voltage: 11 (V) supply - 0.05 (V) ground (I measured DC just because a saw a + and - on the sensor connector), a variation in the supply of about 400 mV while spinning the wheel. I found it has 2 states like HALL sensor. If you move the wheel very slow to catch the hump it will make the change of 400mV. I couldn´t see the teeth or humps in the sensor hole or by any angle.
-The front right sensor did nothing, pins and the harness side were good.
Hope this will help someone or just for the discussion and of course I would very much appreciate your opinion Paul.
Nice to watch who's giving good explain, not like many other useless mechanics who can replace without any investigation... And can't explain where problem was... Good job😊
I'm a hobbyist. But I have bought my Autel Maxisys, and are getting me an oscilloscope. This is the second video I watch from you, and I can see that I will learn alot from your channel. Thanks
thanks man!
Thank you very much for the lesson. I change the steering knuckle an a Audi A6 C6 and become a failure on ABS Sensor. New Sensor without success. Trying to test the Sensor out of the car was, with the description from Hella not possible. Thanks to your video it works. 8-9 Volt on supply with a 450 ohm resistor in series and AC coupled Scope direct on the Sensor works fine. Presence Signal with 1.43 Hz and clean rectangular signal o Spinn . You save my day!
Awesome!
You are the great teacher and asset to the automotive world.
Hi Paul,
I've worked on 2011 Volvo XC60 today and I've used well instructions from this video:) great job sir, I've also tried bypass test on supply wire and you were right it is pull down design- I could clearly see wheel speed change by tapping back probed supply wire with incandescent test light - surprisingly it wouldn't do that with LED test light. Unfortunately I couldn't really see 400 mV voltage change as I've only have Fluke 123 scope meter even using A/C coupling - I've seen some fluctuations anyway:) These Volvos are using one different wheel speed sensors on RHF wheel ( white colour) then the rest of the wheels (black coloured sensors ) reason for that is that RHF sensor is used to measure wheel rotation direction for correct operation of CITY SAFETY SYSTEM.
Great video again Paul - thanks man.
Cheers.
great tip! Thank you
What do you get KNOWLEDGEABLE and SUBSTANTIAL answers is Sir ScannerDanner
Thank you 🙏
Sir ScannerDanner
From Nick Ayivor from London England UK 🇬🇧
Paul this is one of you're very best video it is informative educational and entertaining I love your style when dealing with the inaccurate flowchart very thoughtful I could see you carving out a career as an expert witness in legal cases about anything to do with the automotive industry thank you so much for this and everything you do cheers
Awsome detail Mr Danner telling where each test lead was hooked during each test
Excellent explanation mate, I have a 2013 Navara D40 STX550, I wasn't able find any faults in my abs sensors using all other test methods including some flow charts.
It was looking like a very expensive fix, with Nissan explaining that all abs sensors need to be replaced starting from the very expensive front ones and eliminating from there.
Luckily I found your master class on this issue and its exactly the same scenario we were following.
Using your method, we uncovered that the newer d40 Navara/Frontier uses the same 7mA-14mA range as the car you were testing.
We found only the rear LH sensor to be faulty and read 0mA, a much cheaper fix
Thankyou very much for posting this.
+Brendan Harsh sweet! thanks for sharing and I'm glad this video helped you
Just ran into this type of ABS magneto resistive ABS circuit on a 2007 Gran Caravan 3.3L. Scanner shows ABS fault codes for missing input signals to all 4 wheels, the RF is obvious, the ABS wire came loose from its mooring point (rusted off bolt attaching to strut) and got damaged. On LF, I backprobed and found the almost battery voltage on one and zero on the other, spun the wheel, nothing changed on either. The back sensors had the small ripple voltage riding on the 10.6 volt supply wire, so not sure why they triggered the no input from those sensors. Currently waiting on delivery of the replacement ABS sensors for the front, will update once they are installed and codes are cleared. Thanks Paul for the video, for conventional testing with alldata repair info would have led me down the garden path for sure!
Meant to mention in my post..since you cannot rely of repair info for accurate information on this type of ABS system, how are you really able to figure out what you are dealing with, if you were not fortunate enough to watch this video? You would be going against all conventional 'wisdom' if you didn't believe what Mitchell and Alldata were telling you.
Thanks Chris! Glad this helped and keep me posted.
Very nice sir. I think you are right that this is the coming thing for ckp and cmp sensors.
FYI, got an 07 Dodge Caravan in yesterday, WSS code. Having watched this video beforehand made for a quick diagnosis.
Hi...I believe the signal is usually represented by change in voltage. The ground wire voltage is constant throughout the process, means that the only voltage change we had here is the wire which has the 10.5 v. That is why I agree that the supply voltage is the supply and signal wire.
great video Dan
It show how things are in electronics in general, when you look at a circuit at first, its not what it seems,
the problems with incorrect manufacture data is rampant, even in the tv trade.
many a day was lost looking in the wrong direction,
on the plus side of electronics, you are forever learning
No, not at all Paul, if anything you deserve praise by no only myself, but your other viewers and your students. I would like to see more starting system variables. I don't want someone to do the bypass test, their vehicle cranks but does not start and they think there is another problem(you either make a left turn in your diagnoses or a right turn) and system variables are going to help dictate that. That is all and oh man, anti-theft(gm's passlock notorious for issues) that would make a great
You're right, I think the better way to reach a decisive conclusion is to do further testing. May be it is time to short the sensor ground with another signal ground and find out if the computer will set a DTC for the WSS. If the ABS module sets a DTC then the sensor ground is the signal wire.
On some of the Chrysler vehicles(this refers back to your older Dodge neon starting system video/lecture, the key DOES NOT have to be on in order for the ign. switch bypass test to work. This is because the computer does not directly control(supply a ground) for the starter relay coil(the reverse light/neutral safety switch, all one assembly) grounds the relay coil as long as the vehicle is in Park or Neutral. In that case, the vehicle, will just crank over(the pcm is not alive, thus the ASD and
Hi Paul well I think you done the right thing in testing the circuit explained what done what etc, you cured the problem with a new sensor, think it's a case of what have you got and how does it work and what does what...Fred uk.
I think you guys are on the right track the ground wire is signal wire that's why the schematic labeled ground as signal. If feed wire was the side CAB was using for reading speed signal you could use external ground I think. My bet is that ground is the signal.
I believe the CAB detects changes in CURRENT on the signal wire, I would think if you have 12 volts on one wire and a ground on the other and there is a small current square wave on both wires the system is working correctly Fred UK.
I had the same issue acquiring a clear scope signal on an ABS speed sensor on a late model Jaguar X-Type after seeing no left front speed signal on the data list. I had to AC couple the signal so I could set my volts per division down to a level that would show the digital signal. Very low voltage switch on a good sensor (right front). The left front hub bearing was in backwards (internal reluctor).
wow, thanks this was just what I was looking for. Replaced rear wheel hub on my dodge journey and it came with an another type of abs sensor than the original. Luckily the connector was a little different, can't imagine whatever could have happened. Used the old one instead. Greetings from Finland 😊
great video. wouldn't their also be a small sqaurewave on the 06 Colorado supply wire since its between the module resistor and the changing resistors in the sensor?
great info!
I know I'm late but you can measure mA with your scope by looping a jumper wire for your clamp, each loop after the first is X=1 i.e . with a loop of 10 your reading X10 so a 1 mA sig would show as 1A , 20 loops = 2A. this will allow the scope to actually "show you" whats happening'.
This is something I learned with my fluke amp clamp in the late 80's.
And should be the best way to read the newer WSS without the drama.Simply add jumpers between WSS and EBCM with extra wire to allow for your X loops set DSO to approx range and spin away.
hi, do you mean Oxygen sensor by the air/ fuel sensor? if you mean that, then Oxygen sensor monitors voltage (not current) from 800mv at rich and 200mv or less at lean. I think if the computer ground (sensor ground) is shorted with other ground (body ground) we may have a DTC of signal short ground, in case we have a difference between the two ground.
Not at all! I was thinking the same thing while editing this video. "man I wish I would have grounded that ground wire to see the response. Next one I get you can be sure I will do that. Thanks!
The 2008 Caravan uses a Hall effect ABS wheel sensor, it has internal electronics, you will see an open circuit testing it with an ohm meter. You will see 11 -12 volts DC if you measure between the 2 wires when sensor is connected to vehicle and ignition set to on. Leave meter connected across wires as before with ignition on, set digital meter to frequency mode, now rotate wheel and watch for frequency reading, on good sensor I see 40 - 50 Hz turning wheel by hand.
Thanks
I would think if there is a voltage square wave on the positive wire it is being caused by interuptions in current by the sensor.prob. causing a voltage drop on and off, a good way to test it...Fred.
It's certainly caused a lot of interest Paul to say the least...great stuff Fred uk.
Hi Paul a bit heavy going that one, will have to watch it again, bit confused, what do you have on the feed wire without the wheel turning, just 10.5 volts dc or a square wave, if its a square wave is it origanally generated by the computer, can see what the sensor actually does, does it modify the square wave, so the one coming in is different than the one going out when wheel is spinning, have to watch it again, very interesting though....Fred UK.
As you know that pin 4 in DLC represents body ground and pin 5 represents signal ground. So I think there is a difference between the two grounds that can be detected by the computer.
Hi Paul I think I see, you have a 12 volt supply to one wire with a square wave on it coming from the computer, it goes to the sensor and comes out modified relative to wheel speed which goes back to the computer on the earth lead...the square wave should stay the same on the supply lead if wheel is turning or not?? unless it is effected by current flow?...Fred UK.
no problem man thank you. emotions are lacking in this form of communication and I suck at it sometimes. I apologize as well if my questions in return seemed harsh. It was not my intent. Have a great evening my friend.
ive read that your suppose to use a micro current probe, which is also how you test wideband o2s, problem is no body sells them yet and if they do its over $700
Paul idk if your verus is more up to date then your vantage pros but if it is ... cant you look at component tests on it to see if they changed the info? i noticed your vantage is 11.4 mine is 8.4 .
Had 03 Lesabre air bag front end crash sensor code, it used a digital current signal milliamps. used very low current clamp & picked up digital signal on bad & good sensor with initial turning key on. Since these two sensors appear to function almost the same other than one has reluctor wheel and other must have an internal moving part.
I am now wondering if I could have also used the ac mode without a current clamp too at least view the signal with a lower scale on a scope or graphing meter?
The circuit in this sensor is very similar to a three wire only difference is instead of open collector output, the output is a current source of 7mA being switched on and off. The circuit always draws 7mA mostly to power the hall cells. Typically a 100 ohm resistor is used to sense the change current which is in the CAB. This resistor can be on the ground side or the high side of the sensor. It doesn't matter.
I am in alignment with many of the comments below in that this circuit is very similar to the air/fuel sensor circuit.
So far, I only know how to debug an a/f sensors by using the scan tool, snapping the throttle, and looking for a characteristic wave form on the a/f pid. Well, that works when the sensor and circuit works, but what the heck do you do when that test fails... Pain enters the ball game.
I'm still in the process of researching ways to debug this type of circuit. What concerns me is that it appears the manufactures are slowly turning to this type of circuit. I'm guessing it might save on internal circuitry costs in the controllers.
Again, thanks for all of your time involved to share your knowledge and findings.
I just ran into this on a 2012 jeep liberty but get ground on both wires on the harness side. I checked for open wires and shorted wires but they are intact and not shorted. I back probed the pin at abs module with sensor unplugged and still see ground. I suspect bad module. Is there something I missed?
Paul
Kinda curious. Could you of checked a good known sensor and that bad for resistance. Great video. I understand fully. Buy the way. I took your advice at bought a used vantage. Great front door tool. Maybe when I grow up I'll upgrade to the vantage pro
Fuck me 😮 almost fell of my seat. 10 Years makes a big difference. Watched all his new stuff and then this popped up😅. He's definitely gotten better with age 😊
Was this one in need of today's editing? 😅
Okay cool, I understand now. I was okay with the suggestion either way, just wanted to make sure I understood where you wanted me to go. Thanks jarin, I will add it to the list :)
awesome video, im your fan from PERU, i had a problem with a 2008 hyundai tucson 2.0 with no activity from the O2 sensor 1 code, the computer only read the bias voltage all the time, but the weirdess thing was that the pcm was in close loop and my short and long term was in -35% in every engine speed, when it was in open loop the engine was running well, but in close loop the pcm took all the fuel away, i dont understand why it did that?
Because PCM is not using 02 sensor in OPEN Loop
@@dude8165 obviously
nah, I apologize if I came out to aggressively...it has been a long day my friend. I appreciate it.
I have some confusion that I'm hoping you can clear up. I am working on a VW that has the same type of WSS as the jeep discussed in the video. It has WSS codes for both rears and scan data shows 0mph at all times. Both sensors produce a signal exactly like this jeep when spinning the wheels and looking at a scope. My question is, if the sensors are producing a signal, does that mean the ABS module is faulty?
Compare to one of the front ones first. Then let me know what you see
@ScannerDanner I did compare to the fronts and found the same thing, a small square wave on the supply circuit exactly like the jeep in the video. I was also confused at first because the "signal" circuit is just a ground, but the description of operation did state that there is no separate signal wire and that the signal is superimposed onto both signal wires. Could it be that it uses current as the signal instead of voltage?
@@teranluis100 I'd do the same test now at the module itself
@ScannerDanner Sorry, I should've been more thorough in my initial comment. I hooked up the scope at the module as well and the signal is still there. I hook it up to the supply circuit and see a square wave that ranges between 10-11 volts.
Just wanted to give an update, replaced ABS module and issue was resolved. Seems that somehow the module was receiving the signal but not "seeing" it.
Awesome! This definitely will help me a lot with a similar problem at Work. Thanks!! God bless you
Thank you for the great lesson Mr Danner
Thank you for the informative video sir Paul....the idea is very great.,can I asked something sir? Because as I watching this video what comes up my mind is this...for example if we haved a bad wss on a front RH, can we simply disconnect both connectors of front wheel wss, and put a two test probe on a good one wss then connect a patch cord from it and ran that to harness side of the bad wss with already two test probe also connected then spun the hub monitoring wss parameter to react? To tell circuit and module is good?..then conclude sensor problem? Only used the known good side sensor to get information if my circuit and module is good?.....I keep watching your videos sir to build knowledge,strategies,how to approached concerns....thank you god bless sir Paul
is it safe to say when you see an oscillation on the supposed supply wire it is also THE signal wire ?
+Robert Lesaca yes, sometimes :)
the oscillation can actually be from a voltage drop from current flow in some situations. (not so much here with this very low current circuit)
+Robert Lesaca ive seen a video of a loadpro...is it wise to use it in checking power and ground integrity?
Hi Paul I have watched it about 4 times, I think we have come to same conclusion, the CAB supplies 12 volts to sensor and the other lead goes to ground, when you turn the wheel I believe the sensor chops the current up, and you get a small square wave of current on both wires, the voltage wave just caused by a a voltage drop due to current change...how's that, so technically earth wire is prob signal wire - Fred in England.
commenting about the signal wire as identified by the wiring diagrams. could it be that the module is monitoring current flow instead of voltage and they are doing this on THIS wire so they call it the signal wire.
Thanks for the video as always excellent. I am sorry but I am not convinced that the ground side is not also interpreting the amperage change as a signal at the CAB so if there was a short to ground on that side we could have a bad interpretation at the CAB. I am thinking I'd test wave across sensor using the circuit ground as ground and if there is a varying voltage I'd do normal short to ground tests. Possibilities include the possibility that the circuit is broken and shorted to ground. Any thoughts? Am I missing something? Thanks much again for all you do!
you could be right. we will need to do some further testing on the next one for sure. and I already planned on it. I am going to short the ground wire to ground and see what happens.
ScannerDanner my Hantek scope does not support ac coupling, I have not encountered this type of system yet, but do you think if I were to connect the ground lead of my scope to BAT pos instead of ground, could I pickup the signal because the system voltage would be steady and the sensor voltage fluctuates. Therefore the scope would measure the difference in voltage, giving a display of a signal waveform?
+Joe Nause Well just tried it yesterday on a 2010 GMC Terrain and it works!
+Joe Nause I have Hantek as well, and it having only DC coupling is fine, all AC coupling is for is to filter out the DC component of a waveform. DC will pass both types of signal.
Aware of that, but to get more detail on the signal riding on top of a dc signal, you need ac coupling. That is why I went to bat positive and the signal wire. other wise i would only get a 12v line with a very tiny 50mv ripple on the top. Reducing the scale drives the waveform off the screen, but reducing the scale and ac coupling puts the waveform right on the zero line
Far as I can tell, you really only need to see that small ripple voltage for the most part to tell you there is a signal there. I just went through it with my Hantek. Would be nice to zoom in, but really just need to know the signal is there.
Yes, this works very good with the Hantek without AC coupling. The next time i have to work on such system I will try with a condensator ( ? mict farad) in serie.
Of course jarin, I am all ears
Morning Paul, at this rate I can see you doing a follow up video to this one, seems to be a lot of controversy, good luck on that if you do, I think maybe a short to ground on the so called signal wire might be an idea on what to do...Fred.
What do you call INTELLECTUAL AND PRODIGY and SUBSTANTIAL add one more ACCOMPLISHED the answer is
Sir ScannerDanner
My teacher
Start to finish tutorial great thank you loved it
Take care and have a great Evening with all your family around you
PROFICIENT Sir ScannerDanner
From Nick Ayivor from London England UK 🇬🇧
If the wheel sensor is bad, and I go to live data for abs system on a professional scanner, will the bad sensor be showing speed for that wheel? Shouldn't one of the wheels be staying at zero mph when the car is moving if a wheel sensor is bad?
correct, one of the sensors will show no change at all on the scan tool
Thanks...So if all the wheel sensors are showing the same speed, and changing speed with the cars speed, then it can't be a wheel sensor that is keeping the ABS trouble light on? Most likely the ABS module? Brake fluid is full, and all brake pads are at 90%
What codes do you have? If you can read the ABS wheel speed sensor data you can certainly pull codes
Here is the whole story: I am working on a 2003 Lincoln LS V8. I have the ABS light on..Scan tool
shows DTC in ABS as C1998 which is re-calibration of ABS. Is there a
way that I can do this my self without taking it to a dealer or shop?
All wheel sensors are working properly according to live data on
scanner. I think this is due to dropping the steering assembly to the
floor for a while when removing the dash for AC evap core replacement. I
have an Autel MaxiCOM MK808 ..No bi-directional control, but does about
everything else..I just wanted to make sure that the wheel sensors could not still be the problem. I also have Forscan on my computer, so it may be possible to do it through there if the Autel will not. The SRS light is on also, so it may be possible that the clock spring ribbon cable was damaged from the steering assembly being dropped...which may be messing up the steering angle sensor too?...thanks
Great lesson, know system design and if not sure, look at known good one
No square wave unless the wheel is turning
Excellent, thank you, where else would I have got this explained like this? Nowhere. Thank you.
Hi I agree it is usually by voltage but this is an abnormal circuit, it's a wonder it works at all, but basic law of electronics states the current is the same throughout the whole circuit, it always is...FHS.
Why would you put supply and signal on the same wire? why?
Hi Ali, well that might be the way to go, bit of a funny one to say the least, makes you wonder who designed the system, I thought the reluctor teeth looked a bit small...have a good day, Fred in England.
mr danner u have any idea where I can find both plastic sides on my vantage pro (looked every where)
sorry my friend, I do not
Good video, every time I watch one of you videos I learn something thank you excuse me do you know if one of this WSS can power the ESP, BRAKE AND BAS light cause I got a 2007 chrysler 300 with those lights on right now and I dont know if it's the WSS or ABS module thank you in advance
step 1 is to scan it for codes my friend. Typically the red brake light will not be illuminated from a speed sensor issue. The ESP light will though as it is part of the same system. So anytime your ABS light is on, the ESP light will be also. But the red brake light is typically something hydraulic that has failed
@@ScannerDanner Thank you Paul appreciate you answer and you time, have a good day
@@ScannerDanner Hello Paul this is the code C2206 Chrysler ABS Vehicle Configuration Mismatch, I dont really know what this mean but in some videos said the ABS MODULE I dont know if you work in some of this cases and probably can help to me to figure out thank you in advance and have a good day
Let's move this to my forum. It is free to join and is definitely easier for me to help you there as i have paid moderators who are there to help me help you guys.
www.scannerdanner.com
@@homeroaguilar6163 did you replace the ABS module on this? What is the history of this problem?
let me start by saying thank you. your videos are awesome and I learn more and more from you every day.. can I be so bold and ask you a question and what direction you would go.. I'm working on a 96 cat Fleetwood and the ABS and TRACTION light goes off and on...at stand still the MPH all the wheel speed sensors are reading all over the scale. 1- 80 mph at a complete stop... also system voltage the ABS is reading is all over the scale..zero thru as high as 15volts... when the scan tool see voltage I noticed the pump motor turns off and on as the voltage appears and disappears.. I'm a little lost and irritated I cant find a problem.. lack of experience and understanding on ABS I guess.. I have video and schematics. id love to send them to you and my findings.. customer is just going to have to wait.. and I hate getting my ass kick lol oh, vehicle system voltage is good all the time..its just the abs module is seeing an erratic voltage signal...thank you, I know your busy... I would appreciate your input
is this a chrysler or fiat jeep? or maybe a late benz/daimler?
No V on signal wire while 7-14mA on the same wire tells us that there is no resistanse in a CAB on that wire and all the voltage drops at sensor. So, you better dont put 12V on that wire to test it....something in CAB might burn. Am i right?
in others cars with the same O2 problem it was in open loop all the time
Paul, I have a request, but I would like to message you personally. Your class would benefit from my suggestion and of course you would enjoy lecturing on it. It also involves a case study so that would be cool as well. Thank you for your time.
Wow, amazing video sir! Chrysler screwed up REALLY badly on that service information. A typo or a miscopied wiring diagram, I could understand... not blatantly wrong information.
My personal go-to test for single WSS codes involves jumper wiring a working sensor into the harness for a suspected bad sensor, and watch scan data for a response. Is there any reason that wouldn't work with this design of sensor?
Also, enjoying the new format!
speechless, awesome only Paul great video
Hey Paul I was wondering how do you use Mitchell wire diagrams I'm very interested and in how to do your class on line if you do it online and if you give a certificate and end of training ? PLEASE. READ. .. . . .!!!!!! 😃
Chad
I do not offer a certificate. But I do promise you will not be disappointed by what you learn. Thanks!
Fuel Pump Relay are not energized. My suggestion is this, two vehicles with completely different starting systems. You do your ign. switch bypass test on both, explain what you are doing and why one starts and the other does not. The point being, yes the bypass test is awesome and critical at times, but you are only talking about jumping one wire and that not all systems are active doing that. Those differences in circuit design are imperative to know.
So what you are asking me to do is to cover the workings of the ignition switch? And to do it on different systems? There are so many variations. Run circuits, crank circuits, anti-theft involvement, accessory circuits. Computer controlled, non computer controlled, push button systems......
The bypass test I did was to prove the ignition switch was bad on that one system. It wasn't a test that can be done on everything and I do not believe that I led people to believe that. Did I?
just went through this today. spent a couple hours trying to figure out why the known good wheel was not producing a signal, but in the scantool showing speed. here i am at home trying to figure out why my labscope was not producing a signal. going by alldata and outside information, now finding out wrong information. !!!
Glad this helped!
i can hear vince fischelli screaming to put a batt. pack in parallel to keep base system e good and charged, only after of course after you clean the batt terminals and check batt. ground E drops if any
Off topic but you have any thoughts on this I believe its the (PNP)???
VID_20131114_085739.mp4
Wow, that was awsome. Thanks Danner! You make me smarter :-). You fine way of thinking. And i like it.
This is a fantastic video. Thank you so much for this.
Had to work on a Pt cruiser yesterday earnt my $99 AU quickly because I watched this video ages ago and remembered ! Ac couple low voltage scale Cha ching
This is what I'm talking about! I even read this comment to my son last night. Thank you!
Great video again. Really learned something there. Thank you.
Hi Scanner Danner,
I have a VW Golf mk6 cayc with the same type of sensor Magneto resistive, I have identified it with the help of this video.
My problem is I have battery voltage and signal on the same wire for both left/right wheel speed sensors but no ground feed to my Front Right speed sensor but i do for the Front Left.
I did a continuety test from the right sensors ground pin to the abs module connector and continuety was ok. Which lead me to think it was a computer issue. The only evidence I have is that the car has had a rat infestation but cannot see any damage on the surface.
I am getting various codes showing which are 01279(longitunidal acceleration sensor adaptation), 01435 (brake pressure sensor 1 adaptation), 00778(steering angle sensor adaptation), 01423(lateral acceleration sensor)
But my main concerns are= 01314 (engine control module read trouble codes - intermittent), 00285/00283 (left/right wheel speed sensors G45 electrical problem intermittent), 00668 (supply voltage terminal 30 upper/lower limit reached - intermittent) and finally 01305(databus for infotainment - no signal/no communication)
Is there any advice you can give me please? Just seems like a coincidence that it is the left/right front wheel speed sensors acting up and not the rear as they where the only sensors i was previously experimenting on trying out my new ocilloscope checking for signals lol.
Hey, post this to my forum 😉
www.scannerdanner.com/forum/post-your-repair-questions-here/3757.html
You can reply here when it's up. I'll see it. My wife helps me with the support inbox, so we can leave her alone lol
I just happened to be doing some this morning.
@@ScannerDanner Its posted on your forum. Thanks
I love this video very informative
It really sucks when a manufacturer can't get their diagnostics/trouble charts correct - ultimately that means the customer pays for a bunch of extra labor for a tech to figure out how it really works, and probably for parts that weren't needed in the first place.
Great video once again. Ignorance is NOT bliss in this case! Why would manufactures wan't to standardize the digital wss.... (add sarcasm here) that would make it wayyyy to easy to diagnose...lol, Thanks for letting the 'cat out of the bag' Paul and letting us all know how wss work in different ways. Take care
Thanks, I didn't know that. Good information.
Hello. I’m not sure if you bother monitoring comments on your videos from so long ago, but I feel compelled to comment. Also I’m not sure as to what you wished you would have done/tested but didn’t. It’s possible that is what I wish to comment on. As you did mention, it is/was possible for the ground wire to be the signal wire, but it appeared like you were somewhat ruling the out. You noted that you got the same amperage on both wires but no voltage was present on the ground wire. I believe that to be impossible.
Had you adjusted your scanner to the 1 volt range as you had done earlier on the power side, you would have had to of seen the same mil-amp reading. Would you not ?
It is my belief that what you believed to be the ground wire is/was in fact the signal wire.
As it would/is far simpler to measure mil-amps at low voltage than to think you can get a reading off voltage drop from a voltage supply that is never 100% constant.
I want to say I very much enjoyed your video and plan to subscribe. I’m hoping you have videos on testing just the sensor/pickup on various types.
Thank you.
"You noted that you got the same amperage on both wires but no voltage was present on the ground wire. I believe that to be impossible. "
This is a fundamental element of current flow. What enters a circuit, must leave a circuit. The exact same amount. So my point is, you can measure the power side or ground side of a circuit (no voltage on the ground) and read the exact same current flow.
Did I also do a bypass test on this sensor? With a test light? I don't remember. IF I did and was able to trigger the circuit and cause the scan tool to show a wheel speed, then I absolutely identified the correct wire as the signal wire. I'm sorry though, it has been so long that I do not remember. Thanks!
i came across this once before. hard to see it.
Top-of-the-line
Sorry I see where I should have left my comments now. I don't use this online communication much it's so time consuming.
An a radio electronic we call tha a condenser macrofon stremgle senses
We + senal back and front
Condenser microphones
Ress open ohns
Literally walk your students through two starting system wiring diagrams and trace the wire that you bypassed at the ign. switch and show them what it does and what it does NOT power up and all the variables involved.
Thanks a lot good info.
You can Google electric condenser microphone and you will see how it works
exelente
They called " MARK 20E" system.