How to test for a short to ground (ohmmeter vs test light)
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- เผยแพร่เมื่อ 15 ม.ค. 2017
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www.scannerdanner.com/join-sc... Topics cover
- short to ground testing with an ohmmeter
- why a test light may not locate a short to ground
- impedance of a multimeter
- bypass test with a test light
- how to find direction when troubleshooting
- basics of a GM electronic spark timing system
- parallel and series circuits
- Ohms law
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This channel is dedicated to training both the do it yourself mechanic and the professional technician. It does not matter your level of experience, I can teach you to troubleshoot electrical and electronic systems of both cars and trucks, gasoline and diesel. The information I cover is focused on universal concepts, that apply to all systems, in all model years. It is even applicable to other non automotive related systems.
Some basic electrical knowledge is helpful but not necessary. Start with my week 1 playlist to get an overview of my class at Rosedale Technical College. From there you will find coordinated week by week teaching through my book as well as new weekly case study uploads
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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. - ยานยนต์และพาหนะ
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So the story is that the car wasnt starting up because the injectors werent getting a signal from the ECM due to the viper alarm stealing some juice supplied by the ICM to the ECM. Thank you for educating future technicians properly and i admire your passion, keep up the good work!
👌👍
I"M WORKING ON A SIMILAR PROBLEM RIGHT NOW 2008 TOYOTA SCION XB, KARR 4040a, KS9495 4p
any input would greatly appreciated thanks
As a dealer tech with 7 years experience it’s really satisfying watching these videos years later knowing al the answers from experience. This video is a great example of why we learn basic ohms law, watts law and volt drop testing
Paul,Im a diesel tech for over 40 years and I want to thank you. I thought I new it all but Im still learning with your videos Awesome class thanks.
You can find the rest of my Premium videos from my website at www.scannerdanner.com/join-scannerdanner-premium.html
As of 1-31-2020 there are over 420 videos. Hope to see you there!
"ScannerDanner." As an "ex" USAF Avionics kind of guy (who, at 79, is trying to learn the concepts of the CAN Buss system) I have to say your class was excellent! I've taught aircraft electronics, and watching and listening to you in class, brought back SO many memories of those days. Asking those "overhead questions" and then having all of those WRONG answers coming back to you, is - disconcerting! :) You begin thinking, "why don't these folks know these answers! We've covered that, in depth, previously." ha, ha.Wanted to specifically comment on your last discussion with the class about the wire with the corrosion, and using your volt meter. As a young technician (a 100 years ago :) I experienced that situation, for real, on an airplane's Rudder Trim position indicating system. I had an 11 Meg Ohm meter with me at the transmitter (a 28V DC system). I disconnected the transmitter's connector and read the power input to ground - was 28V DC. So, I thought, bad xmitter. Installed the new one - did not work. Fussed around for awhile, then an "aircraft electrician" friend of mine came by and asked what the trouble was. Explained it all to him. He reached in his pocket and handed me a 28VDC test light with two leads. Connected it to the connector's power socket and ground socket. It DID NOT light. Friend said, you have a high resistance connection in the wire - probably a corroded terminal (it was)
Must tell you, before I did anything else, my friend took a piece of safety wire and stuck it in the 28VDC connector socket and touched the other end to the airframe and asked me to see if the circuit breaker was "popped." It was NOT! Found I had a 20K corroded terminal in the belly of the plane. - that 20K was a BIG resistor. NOW: Moral of the story. The SUM of the voltage drops must equal the applied voltage in a DC circuit. True. With the xmitter in the circuit (ohmic value of around 300 ohms) most all of the circuit voltage was dropped across the corroded terminal - nothing left of the circuit voltage to operate the xmitter. When the Meter was in the circuit, the 11meg of Impedance dropped the majority of the 28Volts - the small remainder now dropped at the 20K resistance. So, it APPEARED that the circuit voltage was fine, but it was NOT. Always carried a test light with me from then on.Had to tell you about this, as this is exactly what you were explaining in your class. Thanks, USAF, MSgt. Ret.
Michael Donavon they don’t have test lights in our boxes anymore lol
Good job
This video should be required viewing for every high school science teacher & student, electrical-mechanical tech, and ENGINEER out there...!! Many still don't get these concepts, or not well enough to put the knowledge to use in real time (to competently do real troubleshooting / work with-efficiency)...
...Too... Your focus on comparing a circuit with low resistance vs a circuit with high resistance and specifically noting the effect of your body on circuit resistance readings in each of those scenarios makes it super clear and easy to remember... Showing the related math calculations shows a genuine connection between the real world and mathematics & aids learning...
...Also, showing the MANY ways to get measurements and conclusions and next-actions wrong thru improper grounding and hookups and logic is going to save many people time and money and effort (and likely-embarrassment) by avoiding false starts / false conclusions...
Thanks for "showing all the work"...
Sometimes folks learn best when the instructor follows the side routes that the instructor really didn't want to get into but does anyway (like you just did!)...
thank you so much! I never check the comments on this channel anymore since everything was moved to my website (TH-cam used to host my paid channel before TH-cam Red and then forced me to move it) anyway, I really really appreciate this comment
I have a M.S. in engineering and have also have been a mechanic my whole adult life .
Very high quality instructor.
Excellent work Thanks
Nice dude. Proud of you man! I hope to be you when I graduate.
@@hitzoneproductions7858 Math Physics master it...Be intense.
Feynman lectures a good guide.
If it wasn’t for this guy he’ such a gift from god I wouldn’t be able to fix the car ❤
2.7.17. Paul I can't but wonder how many techs at dealerships would not of been able to bird dog that viper issue! A great case study!.....Those kids in your class really have yet to fully appreciate your teaching style/methods, but when they are out in the real world with real problems, they will come to the realization of what a superb instructor they had! 👍🏽🇺🇸. "Learn it, use it, pass it on"
Thanks so much Steven!
What’s with the low outlook on dealer techs, I’m one of those dealer techs , we constantly get cars that do the rounds to independent workshops, chasing an issue that can’t be fixed, finally ending back in a dealership with extra problems , ie musical chairs , the tech draws the short straw , and is answerable to about five people above and cannot pass the job on .
@@terrymc5180 yeah was thinking the exact same, I’m at a dealer and would have started with a short to ground test with my meter way before deciding to touch a test light on an input to the ecu lol. And we also get loads of cars from independent ‘specialists’ that are misdiagnosed that we manage to get to the bottom of without firing up the parts cannon 🤷🏼♂️
TEACH IT & PREACH IT
So a good wire will read OL, what type of readings do you typically get on partial short to ground?
Few moths ago I watched this same video I understood little , but now I am washing your Chanel and got your book and is more easy to understand. I’m not native English speaker but you are great teacher and a great person, I wish to leave close to your country to attend to your classes. God bless you Paul.
Awesome video! I’m an electrician and this method of process of elimination is used everyday. You hit the nail on the head with this video!
Thank you! Don't forget this channel is being shut-down by TH-cam but you can find everything here now
www.scannerdanner.com/join-scannerdanner-premium.html
@@ScannerDannerPremium wait why are you being shut down?
Love the case study. This is why load testing a circuit is so important. Always load test circuits. I have seen a few thousands of an inch of corrosion do the same thing.
Man you make me want to fix cars. I used to be a back yard mechanic know I'm a landscaper. Whell owning my own work trucks there is always issues that I cant afford to pay a dealer. You have taught me so much and want to get back into it.
I wish i had a teacher like you Paul.
I had a similar case of good spark no injection pulse, I end up being a missing power at the ECM. It has 2 powers directly from battery and 1 from fuse box, fuse was good but female pins had corrosion. That same fuse also powers check engine warning light. Vehicle came from another shop, they putted a new fuel pump, ignition module, hot fuel module, 2 new distributor, ignition coil. Most of my diagnostic skills that I use everyday I learned from Mr. Danner by watching both of his premium and free channels and reading his book. God bless you Mr. Danner and thanks for your magnificent work. (89/Chevy/silv)
I had a similar case that kicked my ass a few year back. In my case it was a remote starter that had failed. This module was deep inside the dash behind the climate controls and the antenna was hidden cleanly between the roof line and windshield. Customer had no clue and no remotes (used car also). Found a resistance to ground of about 2k. Followed the wire and found the splice. Took me a little longer than Paul to find it... ok ok a lot longer... but I found it. Never have I seen a remote so well installed. I doubt I'll ever see that again, but I have learned from it and this video brings so much clarity to the hole thing. I finally fully understand what was going on.
Thank you
Well I wish there was someone I could trust close to me because I have a Honda accord that keeps blowing the FI ECU fuse and I changed the fuel pump, the crankshaft position sensor, the main fuel pump relay, fi ecu relay.....still blowing the 15a fi ecu fuse. I just don't know anyone that knows what they're doing that isn't going to charge me more than the car is worth trying to hunt down a short. It's a beautiful car. 2004 with 100,000 miles. Ready to send it to the junkyard.
@@ozziecrosby2092 Those can be tricky to find specially if it is intermittent issue like a short that only happens in very rare specific circumstances. Does the fuse blow inconstantly and predictably ? Also was the fuse box check for internal corrosion ?
@@1202Sid..... About 2 weeks ago, I was sitting at a KFC eating my lunch, I had the radio and the AC on. My phone was plugged in. Car was running fine and it just stopped running. The very first thing I did was disconnect the battery and reconnect it, thinking maybe it was the crankshaft sensor. When that didn't work, I had to have it towed. When I turned the key and didn't hear the fuel pump, I just assumed it was bad. Changed it.That didn't work. Going on to a few forums I kept seeing references to the crankshaft sensors in these Honda's going bad and blowing the 15 amp fuse to the fuel injection. Replaced it....still no start. Replacing the main fuel pump relay and the main fuel injection relay didn't work either. As soon as you turn the key to the on position, the 15 amp fuse under the hood blows. I'm hesitant about sending this car to a shop and paying over 70 bucks an hour to chase this problem. The car is a cream puff. It was owned by an old lady that had it since it was new and never drove it in the winter. I would hate to think that I am going to have to send this thing to the junkyard with just over 100,000 miles on it, but I'm about to. I certainly don't want to see somebody else driving it after finding out that it was something simple. And, to my knowledge, there's no alarm.
@@1202Sid... Hey!! So after throwing about 300 dollars in parts at it, I had it towed to a shop. It was a 30 dollar idle air control valve. That's what was popping the fi ecu fuse. So mad. 🧐 All the forums I have been on and I never heard anything about the IAC valve. Oh Well.... live and learn....😏
@@ozziecrosby2092 Hello ! Thks for sharing the solution you found to that fuse problem ! Hope you kept the parts that you changed without reason as spare ones ! At the end, you didn't loose that much as you saved your car from the junkyard ! Enjoy your driving !!!!! Cheers ! 2020-05-19
How is it that practical, real world people lecture much better than professors who very often 'profess' to know so much. Dan is a very good speaker and lecturer.
Thank you! My name is Paul Danner btw :-)
Nice class Paul. If they listen to you and watch your case studies they will learn a lot!
As an electrician before we perform an ohm test we do a lead test by obviously touching the leads together and seeing that 0 ohm reading .
Great lecture! It must be hard to keep on subject sometimes with the questions and all, but you pulled it out as always. Thank you for your patience!
Thanks brother
Good teacher I like your knowledge I need more from you from the spark pluugs pls tell me more thanks
Wow. This lecture saved me $3100 in repairs quoted by the dealer to fix why I had no spark and no injector pulse. You are my hero. Here I am 2 weeks without my car to make it to work taking Uber to and from work but this gave me the knowledge and information to diagnose and troubleshoot things myself. You take donations? You deserve it my friend!
Glad it helped! I do not take donations, just follow me on my regular channel, like and subscribe and share with your friends is all the payment I need. Thank you!
"ScannerDanner" is my main YT channel name. This "premium" portion has been moved to my website.
I'll be watching this same video over & over again until it sinks in. Thank you for posting it.
Your students, with their line of questioning seemed to sidetrack you for a time, but I'd like to bring you back to this important question at the point of sidetrack: You mentioned that if the circuit DID NOT have a short to ground that the meter would max out and read ohm with an ohm sign ... so now the question... What would the meter read if there was a short to ground when testing on the wire/circuit in question between the ICM and ECM? .. thanks for a great tutorial.... I knew you were a great mechanic but seeing you teach this class, I was amazed at you abilities to get things across.. many thanks SD
Zero?
This circuit had a 900ohm short to ground on it through an aftermarket viper alarm system
Enjoyed the video Paul as always!
Don't sweat the formulas, learned magnetism and electronics in college physics and could not remember that formula either. It was great to see the practical application in automotive troubleshooting. I have always been frustrated with my inability to apply the college education to this. This video was very helpful, heck it was really good. Thanks.
I wish i had the chance to learn in your school, iv had to teach myself along the years as i follow and you ask your students i normally have the right answer, without any formal training. By Gods Grace. I still am learning as i go along in the field and add more understanding and depth as i learn from your videos. Thank you for your time and effort you put in sharing your knowledge. God bless.
You can join me here! www.scannerdanner.com/join-scannerdanner-premium.html
Great case study. The ohms law math for parallel resistors is 1/ref= 1/# + 1/#. So, the reference resistance would be 1/12 + 1/400,000. Then, the reference resistance is 1/0.0833= 12.048 ohms. You’re an excellent instructor.
Very KNOWLEDGEABLE
Thanks 👍
Sir ScannerDanner
From Nick Ayivor from London England UK 🇬🇧
I thought, "I have to wade through 40 minutes on my phone to find the test method!?" 10 minutes in and I'm wondering if I should tell Toyota I want to transfer from my corp seat to service garage. Brilliant, sir!
Great video as always Paul! Dude, seriously I can’t thank you enough for all the stuff I’ve learned watching your videos. I don’t know why I wasn’t subbed before, but I am now. Keep it up bro
Paul when i listen to you it hurts my brain you are God of diagnostic.
lol sorry about that mikembz1
Paul did you have a video on that van with the viper alarm system? I swear I saw it before. If so can you provide the link?
Directed (Viper) wire color violet/white is tach input on their remote start systems. Has no alarm function. They only cut the crank wire.Probably was a combo alarm remote start.
If the wire got chafed to ground or something went bad in main module of the r/s it would cause this.I diagnosed a car (camaro) long ago where this happened. Installer did not grommet the purple/white through the firewall. Just drilled a hole and called it good. Wire started to wear through and the car would barely run. Love the Vids! Thanks
Just like SD said, regardless of the resistance in line, the voltage makes it through. But once you connect the non-infinite internal resistance of the voltmeter to it, the voltage will drop according to Ohms law, because current is flowing, posdibly really tiny current, but still there, leading to voltage drop.
The plastic on the outside of a positive battery cable is at 12V, but the resistance of the plastic is incredibly high, so very tiny current will ever flow through it.
There are no perfect conductors (at least not at room temperature), and there are no perfect insulators, just very good ones in each category. All conductors are insulators to some point, and all insulators are conductors, it's all a matter of perspective.
If your only going to learn one way to calculate parallel resistance, learn the inverse rule. It works for two or two thousand parallel resistances. Never forget that the total resistance will always be less than the smallest individual resistance with parallel resistances.
I REALLY wished I would have had someone that ACTUALLY TAUGHT class when I was in tech school. My instructor ONLY lectured class on electrical. We were left with our text books for the rest.
outstanding tuition !!
I am so glad I found this video, this helped me alot thanks
Any advice on what kind of a icm to use in the gm’s as a replacement ?
Aww man im excited!!! Just found out about your online course and ill definitely be starting next month! I've been working on vehicles for sometime now even went to my local ComColl but didn't finish due to a back injury. Im going back but ima learn so much from this course in the meantime! I really enjoy all the TH-cam vids keep up the excellent work!!! Looking forward to classes and future content 🤘👍
looking forward to having you Tom!
What an excellent case study! When you told the story of missing the high resistance short to ground and replacing the ICM, I thought, I would definitely have made the same mistake. The only thing better than making a mistake yourself to trigger hard memory is watching somebody else demonstrate the same mistake. There had to be internal inline resistors on both the ICM side and the ECM side. Extra resistance inside the ECM allowed the natural signal to bypass the ECM on its way to ground, and extra resistance inside the ICM dropped the square wave signal to an undetectable level when you looked for the signal initially. It had to be a 'Goldilocks' resistance at the short -- too low and the scratch test would not have triggered fuel injectors, too high and you would have detected a signal when testing the wire initially.
you've been binge watching haven't you :-)
As we speak, ha ha, the goal is 10,000 hours including shop time.
Excellent lecture thank you so much.
Scannerdanner you are incredibly. I'm one of your new student; God bless you 🙏
What do you think of Dan Sullivan? And the Load Pro?
I know I've seen one of your training videos where you explain how an open circuit with super high resistance reads less that source voltage due to voltmeter impedance. Just can't remember which one. Thanks for the vid.
an open circuit with super high resistance -----no such animal you can not have an open and high resistance at the same time
aww thank God. i miss ur in class lectures. back to ur old days, lol
Pdub? Is this Tom? What's your name bro. It's on the tip of my tongue
Patrick I'm also on ur fb page
This video is totally and utterly fascinating and educational you know Paul I have been fixing computers for 15 years and I thought I knew a bit of stuff about resistance voltage etc but I have learnt more from you in the last month then I have in all that time thank you
IS this how you found me brother? I never check these comments here anymore
@@ScannerDannerPremium yes I think so Paul I was so impressed by this video that I decided to do all that I could to help you in your mission to improve lives by educating people so that is why every now again you get a little donation from me
@@nigelstringfellow5187 I saw at least one, maybe two more this month. I really need to get you a direct link for this fund from my school, so I don't have to be the middle man! I will work on that for you okay buddy. I really appreciate this though, so much!
@@ScannerDanner Paul I sure hope that I didn't create extra work for you,Thank you for all that you do for your students and community,As an aussie with an American wife I appreciate your efforts .Cheers.
.some time i watch your videos .you're awesome
good explanation
thanks
You were on the right track, it is product over sum , a 3ohm and a 2ohm in parallel = 3x2 = 6ohms , 3+2 = 5ohms, 6 ohms ÷ 5ohms = 1.1ohms .
Sir your 💯 % right on last meter voltage drops that point ,👍
MAN SCANNER DANNER YOU ARE BAD A$$!!! I have learned soooo much just watching your videos. I can't go to school at this moment, however these kids have sooooo much of an advantage to learn and do something with their lives, but don't take advantage of the situation... I wish when I was growing up we would of had TH-cam or OTHER RESOURCES to learn.......
Superb Paul,you really are gifted at teaching 👍🏻
Thanks Steve!
Excellent lecture Paul. My note books are getting full!
sweet!
Hey Paul as part of an electrical class extra credit project I showed how the parallel circuit fraction equation is derived from simply using kirchoffs law and ohms law. I'll post it on the forum it's not as mysterious as people might think and involves simple algebra
Yes I'm qualified. I attended TH-cam uni. I have a combined experience of 100 years from watching people try things.
Wonderful and smart, That is Knowledge with teaching skills. Great job
I met the same situation with meter impedance when measured voltage on low current circuit.
I had wrong measuring due to low impedance my meter. It must be 10 Mohms or more.
where was this guy when my stupid truck started acting possessed? Great video man
Hey ScannerDanner love your work, i have an issue, my alternator gets real hot when running However it chargers fine 13.9 to 14.5 volts while charging but it gets hots in the process i dont think thats normal, any pointers you have for me.
Now I'm never done this so it might sound crazy but I just want to know if there's a color code that you could show video on for a 97 Grand Cherokee Limited 4.0 l 6 cylinder 4 PCM
fantastic , just brilliant stuff , always said if you have a great teacher that can put it to basics so that everyone can understand , real champion this guy.
Thank you so much Raymond!
Good teacher good knowledge pls help me out how does spark plugs work thanks
Amazing i missed this video. I had paised with the class as Paul had asked what is wrong with just connecting the meter leads to the end of the wire. Its not a short to ground test. Makes sense. First you set highest rating on ohm setting and then with neg touching body of car, touch other leed to another part of the car to test neg connection good. Then pos touch leed to test for shortto ground. Awesome I never knew this. Now I do.
@scannerdanner should I have 14 volts on a body ground with engine running??
Good knowledge thanks sir in Peugeot diagram we have two or three ware which one can put the test light on thanks sir please feed me back
so if asking to check a wire for more than 6000kohm, OL is a pass?.
Great stuff as always danner thanks so much
Thanks Seth!
Hi, Awesome video! i have a quick question... if you use your multi meter in ohms and you grounded to the battery negative post...is it okay still? I know you've said to look for a good metal ground, im just curious to know, thanks
Thanks SD.
Very knowledgeable guy great channel 😊
at 36:35 mint ,the only way to prove your point that open circuit voltage is equal to voltage source no matter what resistance value you have ,is to use labscop,As you said multimeter internal resistance will create current path which will create voltage drop less than Voltage source .bottom line a wire without a load (no current flow) voltage reading should equal source voltage..Good video ..no body should argue with you ...you are a great teacher .
Thanks man. Actually the lab scopes I use (pico, verus, vantage) have less internal impedance than a DMM. Somewhere around 2 mega ohms? So the lab scope would actually drop this voltage even more. But the rest of your comment was on point. Thanks!
I am watching from Turkey ...thanks for useful knowledges
About how much resistance needs to be ahead of the voltmeter lead before the minute current flow in the meter causes a lower than expected voltage measurement?
You are a Great Teacher..
Thank you my friend
If the square wave is 5 volts and the test voltage is 12v, does the 12v not harm the ECM? Excellent teacher.
When did he put 12 volts on the 5 volt circuit?
When he put it to the battery to touch the 5v ref? 😂
Well the 5v ref circuit has an internal resistor protecting the circuit, but he is using a test light from the battery. The load on the test light turns into a series circuit decreasing voltage on that circuit.
@@shootinstraight2299 well that is the valid reason. Thanks.
@@shootinstraight2299 how would you know if the resistor is in the ICM or ECM ? I know Amps go through the entire circuit- so will the resistor create the voltage drop no matter the location or input voltage of 12?
Otherwise couldn’t you accidentally put 12v downstream of the resistor? Or will ohms law apply for the entire circuit
Amazing video Paul
Good job sir. I liked your lecture, very informative. Keep up the good work.
hi does not have to do with meeter measure id like to ask if someone know link or info to the touch presentation screen thanks
great video paul, as always cheers from ontario can
Thanks brother
I have a question Paul. When this scenario happens at a garage you work for do you refund the price of the module you instructed them to install ? How do you build trust back with that garage after a bad call ?
Absolutely not. But you will not be making any more diagnostic time when you go back to look at the car again, to see where you went wrong. Building trust? You should have that established already and if it is a new customer and you just told them to replace a $2000 computer and it was the wrong call, don't expect another call from them again.
If the wire was corroded and the signal is weak to the PCM, is this where the load pro (voltage drop test) would come in handy?
Great video , man!
One time ABS-module had green stuff from connector to in te module it self.... wire connector was allso melted a little.
So before fixed ABS module was Installed, i check ABS-wires (dos it just need new connector or little more), why that connector melted. in firsth place?
Car battery was out and my multymeter showd that my main power wire had a conection to the car body even without the fuse in place.
...The melted plastic connector made the connection betwean main earth and postive wire, without metals tushing....
After that learn curve, i allways test connector houseing to the wires before i take down the car to find nothing is outofplace. as plastic(specialy melted one) can make your ohm meter go wild too :D
what you are talking about with the impedance of the meter is the reason you can't use it measure computer IO and should use a logic probe due to its Very High impedance.
GREAT AND EDUCATIONAL VIDEO. 5 ***** DEFFINITELLY. CLEAR AND CONCISE AS DICTIONARY! GREAT JOB AS INSTRUCTOR ALSO.
excellent teaching, my question is, is the 5 volt reference on Ford as well?
The 5v reference in general? Or are you talking about something specific in the video?
Every car has a 5v reference circuit
I found the 5 volt and it's good. My crankshaft sensor wires back to the computer is showing plus and negative. which one can I do the bypass test on? also my data link pin 7 is read 11.56 volt scan tool wont read. I'm read your ebook trying to get through this
is there a reason when doing short to ground troubleshooting we don't use the negative of the battery (if we are working close to it), instead of a metal part of the car?
Nice one.. series and parallel circuit... Good Job.
This is what I love 👏👏👏
This is what I've been looking for
I'm never on this channel anymore. I've moved everything to my website. Would live to see you there.
www.scannerdanner.com/join-scannerdanner-premium.html
Great video thank you from Egypt
Thank you Mohamed!
Question!! So I am doing the test Lea to ground and the other test lead to the wire. With the ecm and the in this case throttle body disconnected, and I get O.L. Reading. What does O.L mean in this case?
Thanks from Lithuania
awesome! Thanks so much from the US
I'm looking videos/tutorials to troubleshoot circuit that aren't 12v but much higher. Any ideas where I could find this ?
I am vary impressed with the way you teach my greetings Hussein from Iraq
How would the refference signal between the ICM and the ECM show up on the DVOM? I imagine it would not show up correctly because of the DVOM not being able to read the signal's voltage changing too fast from 0v to 5V.
Hi Paul, with the Bypass test, why doesn't sending 12v down a 0 - 5v line fry the computer, is it to do with the resistance of the test light? Mike
It has to do with the internal impedance of the voltage sensing circuit inside of the ECM, not necessarily the test light.
WhitwellMike B b
This is some great stuff :D
Thanks brother
Is there a video showing the vehicle being worked on? I'd swear I've seen a video where someone had replaced multiple ICM and they wanted your opinion before condemning the PCM. The video had shown that actual work being done with the pico or verus.
12:08 was very helpful for me: if the TL lights, then the wire is shorted to ground. if the TL doesn't light, the test is indeterminate => we need to inspect the voltage closely and if it's not 0 then check short to ground on the wire out of circuit
Currently have a 2000 5.9 3500 dodge van that keeps on a throwing code for IAC. Unplugged, KOEO have my two powers and two grounds. Engine running, i have three pulsing grounds with my test light. One wire doesn't pulse my light. The troubleshooting steps say I may have a short to voltage. Would a short to ground also cause the same symptoms? And testing for short to voltage, I would use a 12v source instead of a known good ground? Thank you, I learned alot through this video
this is a reverse polarity 4 wire stepper motor. My suggestion is to use an LED test light, with the IAC unplugged and test each of the control wires for a power and a ground (pulsing), while cycling the key on and off. All 4 circuits should show both power and ground pulses. Let me know what it does.
If you want, Chapter 20 lectures cover this valve and it's controls more as well as a case study I talk about with a single bad driver in the ECM. th-cam.com/video/cXRKJECWX8I/w-d-xo.html
very common problem on dodge PCM to fail, internal transistor will not switch enough to drive the output circuit ,replace your pcm that will fix it ,if you use your labscop you will see very small signal (Amplitude )
Paul, think you were thinking about GM bias voltage (.450 mv ) on a O2 sensor being brought down by the meter 50mv or so in one of your case studies ?
I was actually thinking about the 5v bias on a Chrysler O2 but yes the GM 450mv bias would apply here too
I have a 2000 Silverado 1500 4.3l runs then stop and won't start. If I let set for a few hours it will run again. Fuel pump is at 60 psi. and I replaced the coil. Where should I look now?
EXCELLENT
Excellent lesson.