Bad Engine Computer Testing Part 1
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- čas přidán 23. 10. 2014
- Here is the link to part 2 of 2 for this case study • Bad Engine Computer Te...
2008 Chevy Cobalt with a no start, no communication problem. Also no spark or injector pulse. I will walk you through the tests that I use to be as confident as possible when it comes to calling a bad computer.. It is not as simple as people make it out to be. Most people that replace a computer are doing so by guess work. There is no guess work in the processes I show in this video.
For more information on this topic, I have written a “field manual” called Engine Performance Diagnostics which is available at www.scannerdanner.com as an eBook or paper book.
Want even more diagnostic training? Whether you are a DIY trying to fix your own car, someone looking to become an auto technician, or a current auto technician that wants to get more into diagnostics, subscribe to ScannerDanner Premium www.scannerdanner.com/join-sc... There is a 14 day free trial.
On ScannerDanner Premium I will bring you right into my classroom at Rosedale Technical College. You will find page for page lectures taken right from my book as well as exclusive classroom type case studies. What is so special about these classroom case studies? I pull live problem vehicles directly into my classroom and we troubleshoot them in real time, using and applying the theory and testing procedures we learn during the classroom lectures. There is no better on-line training of how to troubleshoot automotive electrical and electronics systems anywhere!
Disclaimer:
Due to factors beyond the control of ScannerDanner LLC, it cannot guarantee against unauthorized modifications of this information, or improper use of this information. ScannerDanner LLC assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. ScannerDanner LLC recommends safe practices when working with power tools, automotive lifts, lifting tools, jack stands, electrical equipment, blunt instruments, chemicals, lubricants, or any other tools or equipment seen or implied in this video. Due to factors beyond the control of ScannerDanner LLC, no information contained in this video shall create any express or implied warranty or guarantee of any particular result. Any injury, damage or loss that may result from improper use of these tools, equipment, or the information contained in this video is the sole responsibility of the user and not ScannerDanner LLC. - Auta a dopravní prostředky
I have never seen diagnostics this deep. Seeing sensor getting tested out for pull down. I have never gone this far but your right there and it's practice. Lol
I Love real time diagnostics because it teaches the obstacles that we in the field may and will have to deal with to get it right. The thought process being narrated is awesome. I learn way better this way. It's real
Thank you! This is what I do on just about every case study I have. I turn the camera on before I even touch the car, so we can capture that real time diag.
Thanks for the comment!
@@ScannerDanneri attempted my own research on the ohm test you performed on the last 2 sensors and still am lacking in my understanding of: 1. What exactly is that reading telling us with regards to diagnostics - I understand an ohm measures resistance but if you are testing resistance between sensor positive and its ground shouldn’t it be basically approaching infinite unless it was on or shorted? And #2 which relates to my first question - how do you know what reading to expect/be comfortable with? Thanks for the educational videos - super helpful!!, I also find it easier to learn listening to your thought process etc…If you or anyone else cares to share your knowledge I’d greatly appreciate it - maybe explain like you would to a 5th grader lol😂
@@TheAbyssGazedBack First question to you. Why was I concerned about a shorted sensor? (this is why I was doing the resistance test between the 5v ref and ground circuits of all of those sensors instead of unplugging them)
Think about it. If you don't know, that is okay too! But it will help me guide you as to why I was doing these tests
@@ScannerDanner i really appreciate you taking the time to respond. Seriously where do you find time in the day? Apologies if the wording of my question was had to follow. I think we may have our wires crossed 😂. I just mentioned the part about doing my own research so I didn’t get 100 people responding that all the information is available and not try to take the easy way out..
I am asking because I find solving these ‘puzzles’ very interesting and I’m hoping you d help me understand. I’m currently attempting to diagnose a crank/no start on a ‘14 Audi a5 2.0t manual transmission.
Also do you or anyone who may be reading this know of a cheap way to get wiring diagrams?
Thanks again!
@@TheAbyssGazedBack this is my full time job these days 🙂
We had no 5v reference coming from this PCM and I wanted to make sure we didn't have a shorted sensor pulling it down. Like in this video czcams.com/video/za13UnpbH7E/video.html
And because some of the sensors were difficult to get to, to unplug, the resistance measurement at the PCM connector, between the 5v ref and sensor ground circuits answered that question for me! As far as resistance goes, I just didn't want to see something close to 0 ohms. Most potentiometers are in the 5k ohm range and you saw some of the psi sensors I think were in the 1.5k ohm range, which I found perfectly acceptable. Proving we didn't have a sensor shorting out the 5v ref circuit and condemning the PCM itself as the problem.
As for diagrams, I always suggest the DIY version of the same service info I use. It's like $20 per car eautorepair.adtrk.biz/?a=10817&c=24&p=r&s1=
Great video. Long, detailed videos are always welcome. Anyone who says otherwise doesn’t have the patience to learn.
I much prefer these long troubleshooting videos instead of, say, a two minute video on how to fix a problem. You learn a lot more. Thanks.
I agree !
Paul...Mr. Danner sir, you, hands down, deserve the "Teacher of the Year" award...no you deserve the very first "Teacher of the Millennium" award. Thank you for sharing. Thank you for caring. Just HUGE THANK YOU's for doing what you do for us! You're the MAN!!!
Thanks so much. Mean a lot
You are like the Dr. House of Auto Diagnostics.
Whoever comes across this video, it’s like hitting a gold mine.
Sir Scanner, Danner, you are the best teacher and I love you !!!
Thank you so much!
I'm being 100% honestly when I say you're the best teacher and best CZcams channel for diagnosing these problems. You helped me diagnose on my car with what 3 different mechanic shops couldn't. Loving the long videos since you show your whole thought process and it helps us follow along and understand everything better
These older videos are oldies but goodies always best to knoe your circuits everything else becomes easy to narrow Down @Scanner Danner
I wanted to just say you have done an excellent job, by far the best on CZcams, totally in depth super detailed, ... wow keep up the hood work😮😮👍👍👍👍👍
I (many others) appreciate how you walk through you test procedures. There are other videos I watch to get my "quick fix" satisfaction. You could check vehicle first then video tape the results with no mistakes but because you are willing to make mistakes and share them with us all is quite humbling. Thank you brother !!!
P
This is way better than Forensic Files.
thank you!
Haha, so true! And that's saying something!
Scanner danner U saved me so much money by this video the same problem happened to my 06 honda civic coup sent to a shop and told me the ECM is blown so I conducted ur method and it showed me that it's giving me 5v I told the head Mechanic that my ecm is good he challenged me for that as I live in Beirut Lebanon here people r so stubborn and arrogant he placed a $200 bet with me and he will fix my car for free if I win so he lost bro I love watching and learning from u man
Good information even when missing the minor steps. Your mistakes teaches your students and viewers.. Over all I like this online video. You're very descriptive and thorough enough to the point one can understand the issue. Diagnosing is the most problematic and time consuming process
Great video as ever ScannerDanner Paul
I had a similar issue on a GM petrol engine. Instead of the control unit going down it was the split wiring supplying 5v to MAP and intake position sensor.. The wire had rubbed to ground pulling the voltage down.
I unplugged the control unit to eliminate then used a test light which would illuminate connected to Batt +.
Dan...I have to applaud you in and for the video's that you do and the pro-diagnosing, etc.. I have watched a number of your video's over the years and have for the most part found them more so fascinating than educational.
Now i'm here for the education! I'm going through all these same stages as you do here. Well, I hope to complete these stages tomorrow Saturday as we are expected to have weather at or about the freezing point outside.
So to compound all of what you are doing but in sub-zero temperatures and on a GM Safari Van>>> Makes for an extremely difficult and frustrating experience to say the least. Thought it would be a simple thing but is turning out to be more than expected. Failure to locate and fix the issue this weekend of Feb 02 2019 during a tropical warm-up to 0c/32f, the vehicle will just have to go into the garage. I have been happy/proud to be able to conduct my own service/repairs "to a point", but in this case, I may have to succumb to defeat by mother nature!
Ok, it's after 10 pm Friday..... Time to sleep on it and watch part 2 in the morning.
Cheers
Oh...No i'm not a mechanic per-say. I have done a lot of mechanic services over the years on an as need basis. In my later teens, I took two years of mechanics schooling, serviced various marine and automotive engines. Things have changed slightly since then!
Thanks for taking the Time to Record, Paul ! K.O.
Excellent walk through and very informative. Keep the videos coming.
Absolutely great case studies.....keeps me on top of the game. Cheers and keep em coming!!!!
Very good video it's always a pleasure watching your videos, as they remind us how not to forget the steps and follow your book, tank you ,and please keep this good job that u always do.
U just made understanding the electrical description in the back of my Haynes manual alot easier.👍🏾
Hey Paul, I'm sure if I was working on this car I would be looking for sensors shorting out the 5V ref circuit too. But as I was watching, I realized that what we need to determine is whether the 5V ref circuit is shorted or if its just dead. So I had a "great" idea how to figure it out w/o disconnecting each suspect sensor. Use a low amp probe on each 5V wire at the pcm to see how much current is flowing on each 5V ref circuit. I don't know exactly how much it should be but I'm sure you could make a rough calculation by figuring the approximate resistance of all the sensors in the circuit. Also this might be were a similar car would help. You could take a quick current reading from it and then compare.
Gentleman, u r good at this mechanical stuff! Respect.
Good education, swapping engine and all this work for a Cobalt seems over the top, though it was only 6 years old at the time, I wouldn't want to own this car though. It shows complex electrical ground problems probably are not for the person trying to fix their own car and require a wiring diagram and the confidence in reading it. What he could have done (though powering the computer without a harness could be tricky), is pull the single computer harness, power up the computer (connect all input voltage and ground), and check some (may one) output reference voltages on the connector. As a shop you want to work and there is no up side in buying a new computer, but as a fix it yourself and facing a $1000+ repair to do this, I would put $300-400 into a computer if I were not getting computer output from the diagnostic plug or (as in this case) getting these bad reference readings, and verified the computer had power (is your computer plugged in).
I like the way you are filming every thing is real and honest that make us learn more so keep it that way
many thanks to you
Thanks for noticing. Nothing staged here, it's all done live.
You are really good...wow. Spending an hour doing a complete diagnosis rather than simply hanging parts. I like your teaching style too...basically you were verbalizing your self talk. It works really well.
Thank you Jerod! My "self talk" is difficult sometimes. We definitely think faster than we talk and I miss things sometimes
It's also important to note that when you put in a junk yard Motor and use that motors harness, it may have a different pin configuration even though the plugs are the same which will cause all sorts of problems. I've seen that a number of times. Good work though at showing what it takes to diagnose an electrical problem on a car. Most customers think there is a magic box that a tech uses that tells them exactly what the problem is. It's never that easy. Keep up the good work at educating people on how to find the source of problems cars tend to have these days.
Thanks Robert!
I haven't watched the whole video yet, but, knowing the wire colors were wrong at the throttle body and that this is now the second engine installed from a salvage yard I would suspect that the tech that installed the engine kept the engine harness intact with the engine and that it may have come from a sister car that shared the same engine. i.e. I would move my testing to the ECU connector and confirm with volt drop tests across the circuits to connector end views. This has saved me in-numerous hours of frustration with budget mechanic swap diagnosis once I figured it out. Just thought I would share.
I've been working on cars and such since a very young age and have seen the days of climbing in the engine compartment (literally) to adjust a carb to what we have today. Your videos are very thorough and in depth. I agree that you should not edit (for the most part) any videos. Sometimes what might seem insignificant at the moment becomes an ah hah moment down the road. Again awesome videos. Just subscribed and look forward to future videos.
Thank you Phil! You will not be disappointed. Between this channel and ScannerDanner Premium, I have close to 700 videos.
Thanks for videoing long scenes. It's awesome seeing a pro work.
great lesson your diagnosis is excellent thank you
Hello I watched your video and I was like watching a great drama movie! I love the way you troubleshoot like I said it was gripping I followed you right through while I was asking myself the questions you were answering them amazing wish I could come down to that school and learn something with you ! Great job !!!
+Mike Nitti thanks so much Mike! Why can't you come to RTC? Would you like some more info about our school?
Either way, you can follow me here on CZcams too! I have another channel that will bring you into my classroom for $10 per month. It is the next best thing to coming in person.
Let me know. Thanks again!
Wow ! I am a beginner. I learned a tremendous amount ! Thank you very much. I actually will need to watch this video again ! Thank You Scanner Danner !
Glad it was helpful! I have hundreds and hundreds more :-)
Great tutorial as usual, thank you for sharing it.
these are great videos, thank you.
Scanner Danner does it again..
When it comes to shorted reference circuits I swear it's always the last one you pull that ends up the problem 😒 🙄 🤣 @ScannerDanner
Thank you very much for your video. I have a question though. How to determine whether the problem comes from the ECU or the wiring harness? I am encountering problems with my Ford Probe GT and I need an answer...
Would it be wise to just cut the 5v ref wire at the computer and measure voltage there to determine if you have a wire/sensor short? Or would the splice cause problems? For the sensors that you can't get to.
Thankyou very much, for this good example of professional automotive electrical diagnosis. Very comprehensive.
+Volatile Motorworks thanks so much!
37:00 - "I have to get those other sensors out of the picture" Easy, unplug the computer, check resistance from the computer connector 5V terminals to both battery positive and battery ground. as long as you don't see a low reading, you know all the sensors on the circuit are good. No need to do all of the physical leg work unplugging sensors.
Right one, that is where I went right off.
Great video Paul!
distributor,coil ,fuel pump, map,just about every thing anyone could think off has been changed even both computers
Injectors or regulator
you are good at diagnosing. when i was watching it i paused it before you did the next step and we thought the same for the most part!
Paul, Thanks for this particular video. The very subject of "how to be as positive as possible that you have a bad PCM" is one I have wondered about for a long time.
I know you have touched on the subject in many other diagnostic videos. I'm looking forward to watching part 2, but this one has a lot of knowledge in it about how to "test pcm's".
It's a bummer that there is not a "universal PCM tester", that would have a bunch of different cables that would cover the PCM's in most cars, that a technician could simply plug a PCM into that would do a series of automated tests.
I assume that maybe some of the companies that do "PCM rebuilding" probably have test rig's like that, that they build themselves. It would not really be terribly hard to design, for an electronic engineer who had a good set of data on how the computer works.
Here is a suggestion for a video that I think would be of very great interst to many, many viewers, I know it would be for me....................
Please give consideration doing a video SOLELY on the concept of how many PCM's are replaced needlessly. I would be very interested in hearing, based on your lifetime of experience and other stories or data you have heard, is what percentage of PCM's that are replaced are actually OK?
I would bet the percentage is very high. I would also guess that in many. many cases the customer ends up paying for the garage to put the new one in. There are many ways for a shop to put a new computer in, then realize the new computer was not needed, fix something else that is smaller and cheaper, and get the customer to pay for the whole thing.
for sure, I'll have to share my experience with that with you guys sometime. great suggestion!
Great legend of diagnostics. Paul d.......
Hi Paul, love the tutorials. I've decided to get back into diagnostics having been out of it for a few years on the strength of these (perhaps you just make it look too easy)!
When testing for possible shorts to ground of the 5V ref. circuits, how about just doing a resistive test at the ECM plug (plugged in - possibly battery +ve disconnected so no stray voltages) on each 5V ref. connection, and probably eliminate shorts with a couple of measurements? You'd be getting a number of sensors in parallel but as long as you don't see any readings less than, say, 100s of ohms, those circuits aren't incorrectly loaded!
Can't wait for part 2!!!
If I have low voltage on my inertia switch and dual tank switch could that be bad eec unit ? I don't have power at my eec testing plug either? 6&2 would not jump the pump at all?
I have a 98 silverado k1500 5.7 and the fuel pump relay burnt pin 30 so I soldered a new wire in and it's still not starting. iv heard if when you turn the key on an the check engine light is not on then the ecm is not working, what should I do next?
This gentleman knows what he is doing.
I'm working on a 2008 saturn vue. They did a double start or double crank now no crank. Scanned it had u0100. Im thinking ecu. And tips??? I jumped the starter relay and cranks checked fuses and relays.
Well explained video, detailed informations, I proud to be on your channel
Hey Paul, thank you for all of the amazing videos, they’ve helped me tons! I have a question tho. So I have a 2010 Cobalt LT 2.2 automatic trans. It used to run excellent and everything worked perfectly. A few months ago I used HP Tuners to write a tune to my cobalt, now it won’t run, start or even crank, no click or anything. Everything else works except my fuel pump and starter. Starter cranks when I jump it @ relay but fuel pump won’t even prime. Lights, radio, etc. all work but my CEL doesn’t illuminate with all of the other dash lights. What all would cause my CEL to not illuminate upon cranking/starting?
well you have a lot of patience i have experience in control wiring in havoc , comveyor systems etc , sometimes i play with cars not at the level you do , it can be a challenge for anyone you are good at it , i love watching you i guess when we get old i am 63 patience is a little short LOL . don't stop love your vids ,,,,
thanks so much!
sir u had a ford explorer 2008 problem is rough idle at stop. i check the voltage at the electronic throttle body input two wire connector it 3.7 v at both wires will it fine ?
or should be 5 volts and the seccond thing is the voltage should present both wires?
kindly give ur suggestion thank u
HI Pleas could explain this problem I have with my car in this cold weather, its diesel car the preheating relay energise glow plugs when I disconnect my coolant sensor only, if I keep coolant temperature sensor connected no thing happened and the car doesn't start, and if I manage to start the car the glow plugs got energised all the time then got damaged. I put a new coolant sensor and stayed the same. many thanks
great as always! thanks paul
If a new aftermarket computer is installed, do these tests still work prior to dealer flashing computer? Have a car with new PCM, no communication to scan tool, not sure if it's because it's not programmed yet or I have a power/ground issue. Any help is appreciated. Thanks
Keep doing your thing brother. Just saw the FB post and it made me see red. Ignore the stupid people man. You are a good man.
Thanks Alot Mr.Danner ,
u r awesome, I learn a ton watching u 30+ vids u speak your thoughts. thank u
+Robert West thanks man! only 570 more to go :)
Hi, Could you please share some feedback? If a car has a Bad BCM? will the car still start? if not, what is the procedure to start the car? Chevrolet Cruze (Diesel) can be taken as reference car.
Danner thanks so much for you video your personality ! approach ! techniques !
are second to none !!!!!! absolutely the best i have seen you have given me insight and pleasure to delve further than i thought were my limitations ! with great enthusiasm
with your video,s to back up i feel confident god bless you and your family regards steve england
Thanks Steve! Merry Christmas
Awesome step by step elimination of inputs and outputs
Thank you!
Hi there. Great video. I am having the ECU grounding problem on my 99 Honda Accord EX 2.3L F23A4 engine. The engine is misfire on all cylinders, and I was able to trace it down to the OBD2 port pin #5 (device ground). Whenever I plugged in the OBD2 scanner in, the engine runs fine. The O2 sensor also always report high voltage which should be oscillating between 0.1 - 0.9V. Right now, I am temporarily shorted pin #4 (chassis ground) and pin #5 (device ground), so the engine is running right now. My question to you. Where can I get those circuit diagram? I am an electrical engineer, that will help me a lot in troubleshooting the root cause of the problem. I really appreciate if you can tell me where to find the ECU diagram.
Working in a 2003 town and country and having intermittent no communication with tcm along with transmission range sensor codes and no shifting of gears. This led me to checking powers and grounds on the tcm. Powers look good, but grounds from block are at .150 V. From there, I found that unplugging the alternator brings the block ground back down to .000 V. Is it possible that this ground is causing the TCM to intermittently not communicate and other issues with the transmission circuits
When you look up detailed wring diagrams like the one shown, what website are you going to and is it a subscription type service?
Brilliant , great teaching skills . Well done
Can a 96 computer fit on a 94 s10 ls 4x4 vortex if the 96 is the same thing but ain't four wheel drive and the 94 is four-wheel drive
My sister's 2008 chevy trailblazer had been possessed and doing weird things like shutting down completely and than turning back on again and all kinds of electrical gremlins. The dealership put in a new pcm under warranty and a year later same thing. Im thinking maybe theres a short somewhere. Any ideas on where to begin testing? I think they just threw parts at it without testing anything. Ill also get more details on it
I wish I found a fluke laying around lol great video
Are you able to connect alLigator alIgator clIps to starter, then touch battery to start or wIll thIs cause ECU trouble? I have a 2001 Honda CIvIc that turns and won't start. I just Installed a tImIng belt. I can smell fuel and have no spark. Any Ideas how to get It runnIng?
I like your all videos, thank you.
Hey Paul nice video I have a question is that procedure the same for all the veichles that have that kind of problem that don't want to start. To check grounds and powers of the computer and then check the 5v refrence on the conectors. Thats my question. Hopefully I can hear from u. Thanks scanner danner.
thank you u are the best teacher.
hi sir I just want to say thank you so much on your vids . do you have a vid on tcm if there is no communication with ECU . I dont remember code's number. may be U1001 if you have please help me with it.
Thanks for sharing friend .
At 3.51, voltage is supply to left pin 86 of relay and engine starts.
My confusion is that will not the current also flow back to the ECM side and cause short circuit and damaged the ecm.??? Please kindly brief info on this particular flow of current, and on the ground side also. Thanks.
great vid. thanks. my problem is I was putting the dipstick tube back in and it sparked a Lot around the alternator and starter. now its gremlins all over. but not right at start up its fine but as the alt turns the volts go up above 15. and haywire. so if the alt is testing good. where do I go from there. should I test again I'm at a loss. please any help would be appreciated. thanks again for your videos. oh and it is an 02 audi a6
So this 5 v reference circuit is like power feed to sensors for example ac high pressure sensor ? And at the throttle body 5 vold reference is feed to position sensor is that correct? These sensors have 3 wires feed ground and signal to PCM.
What you went through in this video it was amazing step by step analysis from the schematics we have to use schematics in our channels however if there's a place to open up the fuse to the computer I would take an external power supply at 5 volts with high current feed it to the computer to see how the computer reacts and see how much current I am drawing
Bro excellent job of explaining everything with detail.... I couldn't like And subscribe fast enough!!
Thanks so much!
Another great video. Man I’m learning lots 👍
You are watching the perfect set of videos for your issue!
@@ScannerDanner Great. The cold front has lifted. Just have to clean the Snow off and get back at her. Can’t wait. I’m excited. Even though it’s just my Farm truck I wanna get this problem corrected. 😁
THANK YOU THANK YOU!!! The dealer quoted $1100 for my 05 Cobalt no start, no codes condition fix. Following your video, I began your diagnostics using my hands (LOL). Turned out to be a broken (S)terminal wire on the starter. $1.49 for 5 connector pack, some black tape, BANG she runs like a champ. Thanks for the $1098.51 bonus!!!!!!!!!
+77camaro unbelievable that you were told you needed a computer to fix a simple problem. These "parts changers" do horrible damage to my field. It actually makes me angry.
Nice job fixing your car my friend and thanks for watching
thanks Paul Danner
if i have a low voltage on the ing pin can i feed it with 12volts
crank n cam sensor no power, no 5volt ref; IAt sensor reads 4.5 volts;tps 2.5 v. was created by andrameda271
No start; ecm shut down the crank and cam sensors after replacing fuel pump. New fuel pump read 50 lbs then I snapped open throttle it shorted. Fuel pump wiring all good test directly to battery, pump works. Their is no pwer to the fuel pump wire color blue blk stripes.
no coil spark either; there is power going to the coils; I don't understand yet how to do power to ground testing; control side and ground side.
voltage dropped test was done to fuel ground it dropped from 12 volts to 9 volts.
All fuses and relays checked including EFI and open circuit fuel relay all good.
I get lost reading wire diagrams blending and confusing afraid to touch the computer.
It would seem the computer is the source?
Help and guide, thank you. I have spent a week attempting to troubleshoot no success yet. I understand you r very busy and may not get your full attention, God bless!
Respectfully,
Alexander Gonzalez.
Great computer diagnostic!
Dan I have a 01 Chevy s 10 extended cab 4.3 with a p0449 code I have replaced the evap vent vavle, purge valve, and cap and problem Will not go away
Great vid mate keep posting 👍
does anyone know why my ford f150 XLT 1994 loeses ignition fire while accelerating?
Paul, help!!! Man 99 crown Vic 4.6 p1409 the Evr is missing feed koeo)Red brown wire.. Ok about 6" inches away from that another solenoid purge vent solenoid is missing feed p0443.dose ecm supply feed?? Or dose it come somewhere else?? As you know ford dose not have anything scribed on power distribution box..
Have you ever used a power probe hook on a 5volt ref problem?
So if you set the hook to 5 volts and tap into the circuit, it beeps if the circuit or sensors are pulled to ground. Then you can unplug one at a time and the beep goes away and probe shows 5volts. Bam, short found!
Hi scanner Danner. I have some advice, u need a low amp or micro current probe. you could have gone to the pcm and tested all out put wires there for current draw to see if any sensors or wires were shorted to ground.
Another thing too, u tested for only voltage at pcm when it was plugged in. What if the pcm failed in a way that there was no current flow capable on one of the input wires?
Any corrosion on the terminals on the plug and computer terminals that electrical spray cleaner can fix? You might have checked that but thought I'd mention it.
Nice work again brother,,so your saying that a high voltage on an egr sensor per say,, with a working computer given a code of higher voltage value than normal would be a ground issue on that sensor circuit?
Hi Paul - fantastic - just amazed at the thought process, lots of variables in diagnostics. I am so glad it's not an iac. LOL
Haha I know right
lol hey! IACs wouldn't be so hard if freeze frame and scantools didn't both conspire to tell the same lie!
Schrodingers Box Still having iac nightmares Matt. Feeling a whole lot better into the future knowing our overlord is looking over our shoulder to keep us on the straight and narrow. Schrodingers mail box without an P.O. box as well, what about the guys without a computer, never though of that one A. Caught a 4 pound trout yesterday , could send you one. LOL Pax vobis.
Schrodingers Box Matt, It's over, We Hope! Stop crying!
I know it! Back in the day the Snap-on scanners had a glitch with upstream O2 s on Nissan. The OEM mode even gave the wrong trouble code! The global mode had it right....nightmare when those things happen. I certainly can relate my friend. But hey, look at it this way, you'll always have that one thought it your head now "is the scan tool lying to me?" It's a good question to ask yourself.
Fantastic video as always. This may seem trivial but could you tell me what test light you used ? Does it have to be LED or computer safe ?
I don’t know how I got here but I’m enjoying it 😂
Glad you're here!
what if my numbers on my car computer are unreadable how would i replace it with another one ?
Some friendly criticism.
When you hitting the car's paint with a metal testlight, you're penetrating the paint, exposing bare metal. Thats where rust gonna start forming, shortly after your repair.
Other than that, great video as always.