I spent 40 years working on General Motors vehicles, and a dealership setting. The diagnosis process included, verifying the problem exist one of the first steps after that was a good thorough visual inspection. Just went around, putting your eyeballs on the harnesses and verifying there was no damaged areas . That was so obvious you may have found that on that visual inspection.. but great work
Many moons ago a wise old master mechanic taught me 99% of intermittent faults are caused by either heat or vibration . Feels awesome to find the answer. Nice job Ivan!
Makes sense. Heat kills electronics and vibration loosens and causes tight wiring to break. Corrosion might be another cause too but harder to narrow down.
You're absolutely correct but of course there's one new variable and it is in the world of electronics and other people touching it that don't know what they're doing causing new problems
Your notebooks remind me of the early days of my engineering career. We didn't have PC's or laptops, we had engineering notebooks. We recorded everything in our notebooks. Was assigned to resolve a safety mitigating issue. Took 2 to 3 months of analysis and experiments to reveal root cause, to cause the failure at will. Back in the day, software was written in assembly. Was fluent in hex, octal, scope, and test light. After much work, I was blessed with the eureka moment. Typed my report on an IBM Selectric typewriter. Was called into a meeting within 15 minutes of submitting the report. My engineering notebook was confiscated, all copies of my report were confiscated. I was terminated. Solved the mystery, major kick to my lower parts. Two days later was working in the research branch with a very significant salary increase.
I couldn't give up on solving the issue. When triggered, the vehicle would go to WOT. The only reliable way to terminate the event was to key-off. Engineers were trained, consumers were not. The issue was resolved just prior to production. My specialty was resolving issues. Mentored fresh lead engineers to success many times. I was a ghost, some loved me, many hated me.
I would absolutly leave a troublesome car in your hands Ivan and pay whatever you requested! This is the way I want a diagnose to be done. No second hand guesses and parts cannon. I wish I could find another Ivan in my county..
Awesome diagnosis. Terrific job Ivan shooting the video so that we all could see what was going on. This has to take a lot of your time but we appreciate it very much.
The reason for the CAN bus to show so much activity when broken is the way CAN bus works. All attached units must acknowledge all frames that exist on the network. If one or more units does not read a frame, the sending unit will immediately start to retransmit. And even worse, the unit that transmits monitors the network while transmitting, so if the transmitter can not read its own data from the network a retransmit it also attempted. On a defect network it will appear as at lot going on, and no one can understand the data.
Or to put it more simply, the problem with a broken network is by definition every part of the network is interconnected; so one small intermittent short to ground can bring the entire CAN down. Ivan asked if there was any way to shorten the process and I think it would be possible, on a case by case basis. First of all Ivan is what I call scary smart; when he runs across data he doesn't understand, rather than being frustrated, he thinks it's "really cool" and it's likely there may only be 1000 or so individuals in the country with a similar knowledge and skill set. In this case, I might have first checked the undercarriage for more chaffed wires. But that is only because of all the work he did the first time. IOW he was facing the exact same problem with the same symptoms and same olm overage and knowing the cause was a chaffed wire on the undercarriage I would have checked the undercarriage for a similar issue. But then again Ivan is light years ahead of my understanding of vehicle electronics and networks and the only reason I would be looking for another chaffed wire is because a chaffed wire is something I can understand.
the communication bus is probably simular to RS-485 where it has packets with addresses and such. and simple twisted pair wiring. Most commercial fire alarm systems have all the smokes and devices connected on the same set of transmit and receive pairs. and can run longer distances with out much interference on the network.
@@bluebirdpod can bus is way more advanced than RS485 based network. On RS485 you need a dedicated master and one or more slaves. On can bus all units can transmit at the same time...the "identifier" bits are the first to be transmitted, and they determine the priority of a message. The bus is effectively wire or'ed so the unit with the lowest identifier is in front of the queue. I have teached this at the local university, so bear with me for sounding like a wise ass
Holy smokes Ivan. That was an intense hunt for what ended up being a rubbed through wire. You methodically went through each connection on the network and tested each until you found the section that was pulling down network can. Then went for visual inspection for the win. NPR King. Long love King Ivan.
It's a comfort to me living in the next county to Ivan, lol. The mom and pop shops around here are good for basic stuff but then again so am I. Speaks volumes this guy brought his vehicle all the way from NYC for Ivan to fix.
@@PineHollowAutoDiagnostics Still fighting the fuel issue you had when you were here. Time to clean out the fuel cell and rebuild the carburetor again.
Once you had found a corrupted CAN signal I would have disconnected the battery and used the schematic to start at one 120R and check isolation from each side to chassis with a resistance meter to be >1kR. If that passes, test the continuity of each wire, one segment at a time using the schematic, until you get to the other 120R. In this case you would have found CAN low to have low isolation. I would then start at one 120R and disconnect each segment from the far end of the CAN until the isolation is good: the fault is then in the last segment you disconnected.
Prices are auction and so high recently even on the non runners. However, I do remember a a few years back I purchases a 2012 camry with 60k miles where someone changed a fuse block and forgot to tighten the bolt down. I bought it for $4000 non running and sold it for $12000. I made good money on that car.
@@higherregion my entire savings for 2 years. I make around 42k a year before taxes so after spending and taxes maybe I save 5k that I would have on hand. Side gigs is what I plan on doing now because a routine job never changes your chance to get more.
Hi Ivan, That one sure took the prize as the most difficult to locate wiring problem, but nothing can hide from you. 🙂 Glad it has been driving now with no problems. You and your family stay safe.
Yes today's technicians need to have a lot of devotion and perseverance I see way too many throwing in the towel throwing parts throwing in the towel and a lot of those don't have the equipment nor the knowledge therefore they should not even be working on the automobiles I still deal with electronics myself I have 51 years under the belt my physical attributes are worn out
Great find Ivan. The CAN buss and other balanced line networks operate on differential signals between the two legs or wires of the buss. Neither of the lines are referenced to ground or line +. Therefore, if you connect one channel of your scope to one side and another channel to the opposite side of the buss, you will quickly see any unbalance such as a grounded or shorted conductor. Data will only appear line to line. We have the same issues and troubleshooting in data communications between cabinets in certain systems used in 911 centers. This is where I have experienced this type of fault in the past. Great job and keep up the great work.
I had no doubt that it was a wiring issue because the problem was intermittent. I suspected wires had to be either rotted and broken or rubbed through and touching. It was just a matter of where it was. Another "no parts required" repair. Awesome job Ivan! And your right about the TPMS. It's not a big deal to reset that system. That only takes a couple of minutes to do. Although, my OCD is killing me on that not so good splice on the EBCM connector. I can't call that truck "reliable" until its fixed properly.
Whew! I can follow your reasoning, gratefully so, but it makes me so aware that "of all the things I've lost, I miss my mind the most"! Throughout both these videos, always at the back of my mind was the initial obsevation that the readings at several points seemed to be affected by car-body movement...
In training several years ago we were taught to check the signal and resistance at pins 6 &14 at the DLC , check for codes, do a visual, then disconnect one module at a time to see if the CAN came back. I do like the separation or dividing of the system that Ivan performs. I see Eric O at SMA does this.
that's were years of experience comes in to play. most new techs would have been sweating bullets! electrical techs are worth every $$$ they make. crazy stuff can happen when vehicles have all this new age technology. with all you know you still find out what you dont know if you know what i mean. keep up the good work!
ivan, it felt like this one took you to the limit. It certainly did me and I think it will be worth a second look plus a review of the PICO waveforms as there is plenty to learn. The look on your customers face and yours is priceless. I can tell you there was a smile and grin on this side of the camera as well. Thanks for Sharing!
This is a great video BUT I’m kind on on the fence on the repair. Those cables were exposed to the weather and the heat from the transmission casing. This is going to be a recurring problem. But then again, you solved it with the least amount of expenditures and the owner is happy. No idea why he didn’t fix the other 2 issues and depart with a zero red codes vehicle. Nothing beats a vehicle w/no codes!! I’m hooked!!!😂
Perhaps the first step, should always be a quick visual inspection of all accessible associated wiring and connectors underneath the vehicle and under the bonnet / hood. But brilliant diagnosis and perfect result.
honestly I only do visual inspection after some tests get me close. especially on old stuff, a lot of really damaged looking connectors and components look bad but work totally fine.
@@jankcitycustoms I agree that there's a balance. We can't have tunnel vision in either direction. But just a quick look at everything involved, just to touch base and know that there's not a giant tree branch shoved in your wires or something random; it's just worth looking at everything at least once.
It costs nothing to have a quick look, and you can do that without the use of any special tools or software. Not all faults are going to be blindingly obvious, but many are. Several hours work, module swaps and reprogramming could've been saved in this case by just giving a visual inspection to all modules connected to the network. (No offence Ivan, and hindsight is always a great thing). Of course the next one won't be at all visible, so each to their own way of working. 😉 Love the videos.
In cases like this I prefer to unplug everything from can and measure resistance to ground, should be in megaohm range if the wiring is truly insulated from other stuff. After that you can start plugging stuff back in and finding those terminating resistances.
That was a tough one but Ivan's laser guided process nailed it 💪🏻 Not sure how much actual time lapsed but I'd charge an hourly rate but capped at a reasonable level as it's a learning exercise after a certain amount. Nice work 👍🏻
Therein lays the crux of the problem. You end up not being able to charge the customer for all the "actual" time involved. Therefore the technician who is on flag [and they usually are] looses their ass on the job. Then there really isn't a "learning exercise" involved unless it's a common problem with the specific model. Most problems are random failures, and you just have to dig in and find the problem wherever it may be.
If a customer thinks that my charges are expensive I have an arsenal of stories about dealers throwing the parts cannon at a car and still not fixing it. It really does get annoying when people come out with the “you only fixed a wire” complaint. No, I used thousands of dollars worth of equipment, thousands of hours worth of experience and found what is causing a malfunction to repair.
WOW! Diagnostic again my friend. BTW the Saturn from Hell is back. P0420. Found the flex joint between the cat and the rear O2 sensor had a slight crack.(Not enough to make it sound load.) It was drawing in outside air. Causing a lean code and the P0420 code. Only problem getting that inside pice of pipe out of the muffler. What a PAIN IN A** that was.
this is one of the few cases where a led test light might be useful due to the voltage and current being soooo low. been burnt by ohmmeters so many times i dont like using them anymore for anything but continuity. scope is great " do the wiggle watch for squiggle". breaking it down into bite size chunks is definitely a good way to funnel it.
Yes, you could have diagnosed this problem more effectively. But you know what they say about hindsight, so it's okay. But when you see the collapsed negative can-line trace on the scope, the next step should be to connect a small test light from battery positive to that negative can-line. It will light up in case of a short to ground. And then you can home in on the short, by disconnecting modules and follow the short with the test light. In my comment to part 1, I stated that a 60 Ohm resistor is needed. That is not correct. Should be 120 Ohm. I'll go there and correct my mistake.
This problem and its trouble shooting is way above my head. I am going to sip the video like a good glass of wine to better understand everything that you did. The solution was so simple and elegant!
👍 Adapt, improvise & succeed. Great work Ivan! In the old days, without all the fancy electronics, a visual inspection was a key diagnostic tool. That’s something that hasn’t changed one bit.
Hey Ivan -- if you haven't done so, I would highly recommend this exercise: Grab two or three multimeters and some resistors or a decade box. Use one multimeter set to ohms to measure an example resistance (say 120 ohms to pick a random number :-) Then use the other meter or meters to measure the voltage or current that the first meter applies to make the ohm measurement. Repeat for some other resistor values. As a teaser, do you predict that the first meter applies a voltage and measures the resulting current, or does it apply a current and measures the resulting voltage? Having a good intuition about the meter strategy greatly helps to understand what happens if you try to measure a resistance using two multimeters at once. Also how the resistance measurement is thrown off by some extraneous voltage or current in the circuit under test. (And as usual, well done on finding the short!)
Yep, that was tough. I’ve seen those Tesla like aftermarket units for awhile and I thought maybe something necessary like a button for traction control wouldn’t be liked by the GM system in the new package. Gosh a simple rub on a wire by the transmission causes this. Now just an all electric vehicle and a mess those would be when something goes a foul. But you got the knowledge and experience Ivan; you got this !
I WAS LEANING MORE TO THE AFTER MARKET RADIO (TESLA SCREEN) FOR THE CULPRIT. THEN I REMEMBERED HE SAID AFTER A BUMP SO THAT THROUGH ME OFF. GREAAAAT DIAG FOR SURE.
Very good diag! I have a process for the GM high speed CAN, start off with basic resistance across 6&14 at DLC with vehicle powered down. I will try and split the system if it does not show 60 ohms. I was always taught to "remove" the terminating resistors from the CAN circuits which will leave each CAN high and low isolated. Then will check from each CAN high/low circuit for resistance to ground, short to voltage, and then check resistance between the high and low CAN circuit to make sure they are not shorted to each other. If all that checks out, I can assume that the CAN wiring is likely OK. But that only assumes that the fault is current and not intermittent. From there you can assume a module is pulling the network down and split the system from there. Sometimes it can be straight forward and others can be a pain!
Great tips Ryan! Do you use the scope to look at the signals on pins 6 and 14? I always save my waveforms and then compare them to see what each type of failure had on the signals. In this case the CAN - looked like it was pulled down to ground, which is exactly what the issue was!!
That is exactly the problem I found with my 2008 Silverado 4x4 Duramax. That bracket rubbed on the wiring harness and parodic short showing a bad TCM. Loss of communication. Thank you for directing me under the truck. Now ABS and brake lights are on. ??? plus, modules that I had unplugged and reconnected are not recognized and do not work. (4x4 dial/switch no longer lights).
Ivan that's one heck of a detective job going through it from the other side of the wall. Next time you will definitely look at all the wiring and connectors first to confirm good routing and no green crusties I'm sure. I had bought a vintage motorcycle that had a intermittent problem whereby it would just die randomly or loose a cylinder periodically. On a tour one summer it blew up the rectifier leaving me with a stranded bike until I could get it fixed. It was then that I was more than determined to find this stupid electrical problem once and for all. When I was removing the harness to check it, there is an area behind the electrical panel you can not get to to see the wires located there until its removed. that's when the issue was found. The ignition circuit wires and charging circuit wires had been moved by someone in the past and not routed properly. In time they had rubbed through on the part they were touching and so randomly shorting the points wires to ground on the metal fender. The same was happening on the wires for the rectifier circuit. I ended up rebuilding the complete harness and making some improvements to the various circuits and wire gauge sizes while I was at it.
good catch had to be wiring you said yesterday it happens when the car was bouncing around probably worse when warm as the insulation relaxed keep up the good work and thank you for the videos, Ivan
While I can't claim to understand all of this, with each video I learn a little bit more so there's hope I will understand someday! I love your videos, Ivan!
Wow Ivan you've really out done your diagnostic skills.. Bravo 👏. Most people would have given up, but not you. Thank you for sharing and giving inspiration. That anything can have a solution. 🙂👍 thank you
I wouldn't have pinpointed the problem more efficiently , and i would've charged the customer by hours with a discount as he's traveled a long way to get to you + because the issues might be related in his mentality, keep up the great work ivan, and i personally appreciate your time and dedication to spread the knowledge that you struggle to gain for free :)
Ivan great diag there is not many shops that would have put that much persistent into that problem trying to fix it they would give up or replace module's . That was a great call on the customer to bring it to you . Thanks again for the great videos and information
I think is not a problem of efficiency (like to save time) but more on being persistent, sticking to the plan and a ton of patience. Then maybe you can charge the customer for a block of 2-3 hours or 4-5 hours, etc. As we saw, during the worst moments you moved assertively to the next plan and sticked with it to the end, wrote your results and moved to the next hypothesis... and so on until you declared victory.
Excellent Ivan! That was a nasty problem to track, and you kept your judgement and procedures spot on. Despite the headache these faults are, they are fascinating to follow on screen :-)
Great Job Ivan! This one was the coolest repair on Can Bus network Thanks for giving Us this incredible learning I wish I could've meet you One day well that would be great day in my life Watching your videos from INDIA!
Hi Ivan, on can network you are going to see 60 ohms even if one of the wire is touching the ground or power. One of the test I usually do is test for 60 ohms an then see if I have continuity with ground. In that case the Can lo was near zero volt on the scope. If you suspected a module and it is in serries in the Can network, you can bypass it with jumpers. Sorry for my bad english!!!! Thanks for your excellente video!
Since I don't do jobs like Master Ivan does. Yet I do repairs. I quote by the hour per the book. I'm a DYI mechanic and mostly tackle some jobs. My brother in law was having issues with his fuel pump shutting off. Then would come back on. I told him. I think we have either a short from the pump to the wiring harness. If admit I did fire the parts cannon. But we kept the original parts. Installed 2 new parts. I did buy one part for him. Problem remained. He took the truck to Ford. They ran a jumper wire to buy pass the pump. They also pulled the bed and cab. They told him the entire harness needs replaced without pin pointing the actual problem. They broke the harness to the pickup bed. They just used butt connectors and called it good and didn't tell him until I found it. He was on a trip up North. Truck stalled on the freeway. The jumper wire. All they did was push a bare wire into the harness and it had fallen out. Every 50 or so miles he had to stop and push it back in. He was so infuriated with the whole screw up. He traded it in. Got a 2020 Chevy and now it's his daily driver.
I would physically connect a 120 ohm resistor across the bus lines to confirm the bus can be terminated properly, then also check the EBCM pins for the presence of the factory termination, and check for shorts to ground / power internally in the EBCM.
CAN bus reminds me of the early days of Ethernet with the 10 base-2 standard, which used the same principle of a multi device bus with terminating resistors and was also a nightmare to diagnose. I wonder why vehicle manufacturers haven't adopted a similar scheme to the rest of the IT industry by moving to a switched or at least hub-based network with dedicated communication lines per device.
The newer can networks can be tricky as some are more fault tolerant than the older single Line networks but with the breakout box it’s quick to test for a short to power or ground but even if you prove that as an issue you still have to locate the problem, splitting the network into separate branches is the best way to go, pulling fuses was smart instead of disconnecting modules, but having scan tools plugged into your dlc can act as another module on your can system for testing. Sometimes you get lucky and find the fault quickly other times you have to keep chipping away at it until you find it, great diag and a great fix.
Witch you need a lift. Like the wizard always preforms a visual inspection of the under side. He would of spotted that in 2 min. Thanks for all your videos Ivan you still a great tech.
That daig was a real head banger. That's how new curse words are created...lol Way to stick with it. As always, I learned a few things from this case study. Keep putting out this great content.
I spent 40 years working on General Motors vehicles, and a dealership setting. The diagnosis process included, verifying the problem exist one of the first steps after that was a good thorough visual inspection.
Just went around, putting your eyeballs on the harnesses and verifying there was no damaged areas . That was so obvious you may have found that on that visual inspection.. but great work
Maybe, but don't TOUCH anything before you hook up your testing equipment and collect live data ;)
Many moons ago a wise old master mechanic taught me 99% of intermittent faults are caused by either heat or vibration .
Feels awesome to find the answer.
Nice job Ivan!
Makes sense. Heat kills electronics and vibration loosens and causes tight wiring to break. Corrosion might be another cause too but harder to narrow down.
In this case someone failed to route the loom properly so add to his words, a careless mechanic
You're absolutely correct but of course there's one new variable and it is in the world of electronics and other people touching it that don't know what they're doing causing new problems
@@cheapers1952 like what? Leaving something exposed to heat and/or vibration?
We have had carless mechanics for ever and its not going away soon
Amazing how such a complex problem and analysis ends in such a simple fix to a simple issue.
Hate these new vehicles,too much to go wrong from so little!!! not enough electrical engineers around !
That is one shiny and clean alternator ⚡️
Your notebooks remind me of the early days of my engineering career. We didn't have PC's or laptops, we had engineering notebooks. We recorded everything in our notebooks. Was assigned to resolve a safety mitigating issue. Took 2 to 3 months of analysis and experiments to reveal root cause, to cause the failure at will. Back in the day, software was written in assembly. Was fluent in hex, octal, scope, and test light. After much work, I was blessed with the eureka moment. Typed my report on an IBM Selectric typewriter. Was called into a meeting within 15 minutes of submitting the report. My engineering notebook was confiscated, all copies of my report were confiscated. I was terminated. Solved the mystery, major kick to my lower parts. Two days later was working in the research branch with a very significant salary increase.
I couldn't give up on solving the issue. When triggered, the vehicle would go to WOT. The only reliable way to terminate the event was to key-off. Engineers were trained, consumers were not. The issue was resolved just prior to production.
My specialty was resolving issues. Mentored fresh lead engineers to success many times. I was a ghost, some loved me, many hated me.
This vehicle had me stressed out. Ivan, you are the MAN! It's a shame that there isn't an Ivan in every shop.
I would absolutly leave a troublesome car in your hands Ivan and pay whatever you requested! This is the way I want a diagnose to be done. No second hand guesses and parts cannon. I wish I could find another Ivan in my county..
Fantastic methodical troubleshooting/diagnostic skills on display here.
Awesome diagnosis. Terrific job Ivan shooting the video so that we all could see what was going on. This has to take a lot of your time but we appreciate it very much.
The reason for the CAN bus to show so much activity when broken is the way CAN bus works. All attached units must acknowledge all frames that exist on the network. If one or more units does not read a frame, the sending unit will immediately start to retransmit. And even worse, the unit that transmits monitors the network while transmitting, so if the transmitter can not read its own data from the network a retransmit it also attempted. On a defect network it will appear as at lot going on, and no one can understand the data.
You're right. They ping to each other a bunch of hellos and the other module responds and such.
Or to put it more simply, the problem with a broken network is by definition every part of the network is interconnected; so one small intermittent short to ground can bring the entire CAN down. Ivan asked if there was any way to shorten the process and I think it would be possible, on a case by case basis. First of all Ivan is what I call scary smart; when he runs across data he doesn't understand, rather than being frustrated, he thinks it's "really cool" and it's likely there may only be 1000 or so individuals in the country with a similar knowledge and skill set. In this case, I might have first checked the undercarriage for more chaffed wires. But that is only because of all the work he did the first time. IOW he was facing the exact same problem with the same symptoms and same olm overage and knowing the cause was a chaffed wire on the undercarriage I would have checked the undercarriage for a similar issue. But then again Ivan is light years ahead of my understanding of vehicle electronics and networks and the only reason I would be looking for another chaffed wire is because a chaffed wire is something I can understand.
the communication bus is probably simular to RS-485 where it has packets with addresses and such. and simple twisted pair wiring. Most commercial fire alarm systems have all the smokes and devices connected on the same set of transmit and receive pairs. and can run longer distances with out much interference on the network.
@@bluebirdpod can bus is way more advanced than RS485 based network. On RS485 you need a dedicated master and one or more slaves. On can bus all units can transmit at the same time...the "identifier" bits are the first to be transmitted, and they determine the priority of a message. The bus is effectively wire or'ed so the unit with the lowest identifier is in front of the queue. I have teached this at the local university, so bear with me for sounding like a wise ass
@@ccmoos I have said it before but Ivan would be a great teacher, if his videos don't end up in some schools sometimes I would be surprised
Holy smokes Ivan. That was an intense hunt for what ended up being a rubbed through wire. You methodically went through each connection on the network and tested each until you found the section that was pulling down network can. Then went for visual inspection for the win. NPR King. Long love King Ivan.
Make sure to put a spoiler to the video in the top comment! Lol
@@ShaneG199 Hah don't read the comments before watching the video! ;)
It's a comfort to me living in the next county to Ivan, lol. The mom and pop shops around here are good for basic stuff but then again so am I. Speaks volumes this guy brought his vehicle all the way from NYC for Ivan to fix.
Totally jealous!
I have a ton of work for Ivan but I'm 6 hours away! The "other" guy in New York doesn't do TH-cam vehicles. lol
@@SuperM1687 How's the old Genie running Jason? Test light throttle still working? ;)
@@PineHollowAutoDiagnostics Still fighting the fuel issue you had when you were here. Time to clean out the fuel cell and rebuild the carburetor again.
Once you had found a corrupted CAN signal I would have disconnected the battery and used the schematic to start at one 120R and check isolation from each side to chassis with a resistance meter to be >1kR. If that passes, test the continuity of each wire, one segment at a time using the schematic, until you get to the other 120R.
In this case you would have found CAN low to have low isolation. I would then start at one 120R and disconnect each segment from the far end of the CAN until the isolation is good: the fault is then in the last segment you disconnected.
Simply incredible, Ivan. How many vehicles, like this one, wind up on the auction block because of a no parts required repair?
Prices are auction and so high recently even on the non runners. However, I do remember a a few years back I purchases a 2012 camry with 60k miles where someone changed a fuse block and forgot to tighten the bolt down. I bought it for $4000 non running and sold it for $12000. I made good money on that car.
@@higherregion my entire savings for 2 years. I make around 42k a year before taxes so after spending and taxes maybe I save 5k that I would have on hand. Side gigs is what I plan on doing now because a routine job never changes your chance to get more.
@@scientist100 An old saying (that I haven't heard in a long time) "You'll never get rich working for someone else."
@@russellhltn1396 though, some people make less and have nice cars and take more vacations. What is it that am I doing wrong? I ask myself.
@@scientist100 Most likely, you're not maxing out your credit cards. You only see their spending - you're not seeing their bank balance.
Hi Ivan,
That one sure took the prize as the most difficult to locate wiring problem, but nothing can hide from you. 🙂 Glad it has been driving now with no problems. You and your family stay safe.
Yes today's technicians need to have a lot of devotion and perseverance I see way too many throwing in the towel throwing parts throwing in the towel and a lot of those don't have the equipment nor the knowledge therefore they should not even be working on the automobiles I still deal with electronics myself I have 51 years under the belt my physical attributes are worn out
Great find Ivan. The CAN buss and other balanced line networks operate on differential signals between the two legs or wires of the buss. Neither of the lines are referenced to ground or line +. Therefore, if you connect one channel of your scope to one side and another channel to the opposite side of the buss, you will quickly see any unbalance such as a grounded or shorted conductor. Data will only appear line to line.
We have the same issues and troubleshooting in data communications between cabinets in certain systems used in 911 centers. This is where I have experienced this type of fault in the past.
Great job and keep up the great work.
I had no doubt that it was a wiring issue because the problem was intermittent. I suspected wires had to be either rotted and broken or rubbed through and touching. It was just a matter of where it was. Another "no parts required" repair. Awesome job Ivan! And your right about the TPMS. It's not a big deal to reset that system. That only takes a couple of minutes to do.
Although, my OCD is killing me on that not so good splice on the EBCM connector. I can't call that truck "reliable" until its fixed properly.
Whew! I can follow your reasoning, gratefully so, but it makes me so aware that "of all the things I've lost, I miss my mind the most"!
Throughout both these videos, always at the back of my mind was the initial obsevation that the readings at several points seemed to be affected by car-body movement...
As usual my man you have fixed the vehicle. You are definitely one of the members of the elite in the automotive profession.
In training several years ago we were taught to check the signal and resistance at pins 6 &14 at the DLC , check for codes, do a visual, then disconnect one module at a time to see if the CAN came back.
I do like the separation or dividing of the system that Ivan performs. I see Eric O at SMA does this.
that's were years of experience comes in to play. most new techs would have been sweating bullets! electrical techs are worth
every $$$ they make. crazy stuff can happen when vehicles have all this new age technology. with all you know you still find out what you dont know if you know what i mean. keep up the good work!
ivan, it felt like this one took you to the limit. It certainly did me and I think it will be worth a second look plus a review of the PICO waveforms as there is plenty to learn. The look on your customers face and yours is priceless. I can tell you there was a smile and grin on this side of the camera as well. Thanks for Sharing!
Just no comment. Great stuff Ivan. That is how a professional diag a problem. No crap. Thanks.
Jason has a great smile! Awesome job Ivan!
This is a great video BUT I’m kind on on the fence on the repair. Those cables were exposed to the weather and the heat from the transmission casing. This is going to be a recurring problem. But then again, you solved it with the least amount of expenditures and the owner is happy. No idea why he didn’t fix the other 2 issues and depart with a zero red codes vehicle. Nothing beats a vehicle w/no codes!!
I’m hooked!!!😂
Perhaps the first step, should always be a quick visual inspection of all accessible associated wiring and connectors underneath the vehicle and under the bonnet / hood. But brilliant diagnosis and perfect result.
I agree. Always start with a thorough visual inspection.
honestly I only do visual inspection after some tests get me close. especially on old stuff, a lot of really damaged looking connectors and components look bad but work totally fine.
Think I would have done jumpers to find a good signal then should be easier to track down the offending section that is causing the failure.
@@jankcitycustoms I agree that there's a balance. We can't have tunnel vision in either direction. But just a quick look at everything involved, just to touch base and know that there's not a giant tree branch shoved in your wires or something random; it's just worth looking at everything at least once.
It costs nothing to have a quick look, and you can do that without the use of any special tools or software. Not all faults are going to be blindingly obvious, but many are. Several hours work, module swaps and reprogramming could've been saved in this case by just giving a visual inspection to all modules connected to the network. (No offence Ivan, and hindsight is always a great thing). Of course the next one won't be at all visible, so each to their own way of working. 😉 Love the videos.
Amazing fix Ivan, what a problem. These shorts can be the worst, so small but yet a big deal, can't see them until you find, great detective work.
In cases like this I prefer to unplug everything from can and measure resistance to ground, should be in megaohm range if the wiring is truly insulated from other stuff. After that you can start plugging stuff back in and finding those terminating resistances.
That was a tough one but Ivan's laser guided process nailed it 💪🏻 Not sure how much actual time lapsed but I'd charge an hourly rate but capped at a reasonable level as it's a learning exercise after a certain amount. Nice work 👍🏻
Therein lays the crux of the problem. You end up not being able to charge the customer for all the "actual" time involved. Therefore the technician who is on flag [and they usually are] looses their ass on the job. Then there really isn't a "learning exercise" involved unless it's a common problem with the specific model. Most problems are random failures, and you just have to dig in and find the problem wherever it may be.
If a customer thinks that my charges are expensive I have an arsenal of stories about dealers throwing the parts cannon at a car and still not fixing it. It really does get annoying when people come out with the “you only fixed a wire” complaint. No, I used thousands of dollars worth of equipment, thousands of hours worth of experience and found what is causing a malfunction to repair.
WOW! Diagnostic again my friend. BTW the Saturn from Hell is back. P0420. Found the flex joint between the cat and the rear O2 sensor had a slight crack.(Not enough to make it sound load.) It was drawing in outside air. Causing a lean code and the P0420 code. Only problem getting that inside pice of pipe out of the muffler. What a PAIN IN A** that was.
this is one of the few cases where a led test light might be useful due to the voltage and current being soooo low. been burnt by ohmmeters so many times i dont like using them anymore for anything but continuity. scope is great " do the wiggle watch for squiggle". breaking it down into bite size chunks is definitely a good way to funnel it.
Amazing work, Ivan. Knowledge, a systematic approach and persistence.
Ivan,
YOU
NEED
A
HOIST!!!
Great video, way to be persistent and find the root cause of the CAN Failure!
Jason is one happy chap, finally
Yes, you could have diagnosed this problem more effectively. But you know what they say about hindsight, so it's okay.
But when you see the collapsed negative can-line trace on the scope, the next step should be to connect a small test light from battery positive to that negative can-line. It will light up in case of a short to ground. And then you can home in on the short, by disconnecting modules and follow the short with the test light.
In my comment to part 1, I stated that a 60 Ohm resistor is needed. That is not correct. Should be 120 Ohm. I'll go there and correct my mistake.
Du hast den mann glücklich gemacht!!!👍👍👍
Great job!!!!
This problem and its trouble shooting is way above my head. I am going to sip the video like a good glass of wine to better understand everything that you did. The solution was so simple and elegant!
👍 Adapt, improvise & succeed. Great work Ivan! In the old days, without all the fancy electronics, a visual inspection was a key diagnostic tool. That’s something that hasn’t changed one bit.
Hey Ivan -- if you haven't done so, I would highly recommend this exercise: Grab two or three multimeters and some resistors or a decade box. Use one multimeter set to ohms to measure an example resistance (say 120 ohms to pick a random number :-) Then use the other meter or meters to measure the voltage or current that the first meter applies to make the ohm measurement. Repeat for some other resistor values. As a teaser, do you predict that the first meter applies a voltage and measures the resulting current, or does it apply a current and measures the resulting voltage? Having a good intuition about the meter strategy greatly helps to understand what happens if you try to measure a resistance using two multimeters at once. Also how the resistance measurement is thrown off by some extraneous voltage or current in the circuit under test. (And as usual, well done on finding the short!)
WOW Ivan! GREAT job finding this fault. Excellent diagnosis and methodical way to track this CAN fault down. Nice teaching job.
Wow you are a genius, I'm always learning from you GM videos. Appreciate you teaching us techs.
You found the scene of the crime (again lol!!!). Excellent logic and technique. Dynamite!
Love how some of the toughest problems are from simple, basic causes. Great fix!
I love the way Ivan traces the path breaking thing in half then half again until the problem is solved never disappointed in his content.
That was a tough cookie - well done...
great logic problem solving a visual inspection is always to look at the worst environment location nice work
A typical high class expert Ivan repair 👍👍
Well done !
Yep, that was tough. I’ve seen those Tesla like aftermarket units for awhile and I thought maybe something necessary like a button for traction control wouldn’t be liked by the GM system in the new package.
Gosh a simple rub on a wire by the transmission causes this. Now just an all electric vehicle and a mess those would be when something goes a foul. But you got the knowledge and experience Ivan; you got this !
Good hunting. Perseverance wins out Ivan.
That was a tough one, good shot I salute you Ivan!
I WAS LEANING MORE TO THE AFTER MARKET RADIO (TESLA SCREEN) FOR THE CULPRIT. THEN I REMEMBERED HE SAID AFTER A BUMP SO THAT THROUGH ME OFF.
GREAAAAT DIAG FOR SURE.
Very good diag! I have a process for the GM high speed CAN, start off with basic resistance across 6&14 at DLC with vehicle powered down. I will try and split the system if it does not show 60 ohms. I was always taught to "remove" the terminating resistors from the CAN circuits which will leave each CAN high and low isolated. Then will check from each CAN high/low circuit for resistance to ground, short to voltage, and then check resistance between the high and low CAN circuit to make sure they are not shorted to each other. If all that checks out, I can assume that the CAN wiring is likely OK. But that only assumes that the fault is current and not intermittent. From there you can assume a module is pulling the network down and split the system from there. Sometimes it can be straight forward and others can be a pain!
Great tips Ryan! Do you use the scope to look at the signals on pins 6 and 14? I always save my waveforms and then compare them to see what each type of failure had on the signals. In this case the CAN - looked like it was pulled down to ground, which is exactly what the issue was!!
Excellent tutorial on can problem diagnosis. Thanks Ivan!
Tenacity! Well done.
That is exactly the problem I found with my 2008 Silverado 4x4 Duramax. That bracket rubbed on the wiring harness and parodic short showing a bad TCM. Loss of communication. Thank you for directing me under the truck. Now ABS and brake lights are on. ??? plus, modules that I had unplugged and reconnected are not recognized and do not work. (4x4 dial/switch no longer lights).
Ivan that's one heck of a detective job going through it from the other side of the wall. Next time you will definitely look at all the wiring and connectors first to confirm good routing and no green crusties I'm sure. I had bought a vintage motorcycle that had a intermittent problem whereby it would just die randomly or loose a cylinder periodically. On a tour one summer it blew up the rectifier leaving me with a stranded bike until I could get it fixed. It was then that I was more than determined to find this stupid electrical problem once and for all. When I was removing the harness to check it, there is an area behind the electrical panel you can not get to to see the wires located there until its removed. that's when the issue was found. The ignition circuit wires and charging circuit wires had been moved by someone in the past and not routed properly. In time they had rubbed through on the part they were touching and so randomly shorting the points wires to ground on the metal fender. The same was happening on the wires for the rectifier circuit. I ended up rebuilding the complete harness and making some improvements to the various circuits and wire gauge sizes while I was at it.
I had a smile that wouldnt go away, great work Ivan, NPR!!!
good catch had to be wiring you said yesterday it happens when the car was bouncing around probably worse when warm as the insulation relaxed keep up the good work and thank you for the videos, Ivan
You killed it bro
Excellent understanding of the communication system
While I can't claim to understand all of this, with each video I learn a little bit more so there's hope I will understand someday! I love your videos, Ivan!
Wow Ivan you've really out done your diagnostic skills.. Bravo 👏. Most people would have given up, but not you. Thank you for sharing and giving inspiration. That anything can have a solution. 🙂👍 thank you
I wouldn't have pinpointed the problem more efficiently , and i would've charged the customer by hours with a discount as he's traveled a long way to get to you + because the issues might be related in his mentality, keep up the great work ivan, and i personally appreciate your time and dedication to spread the knowledge that you struggle to gain for free :)
In the area of NY I would check plugs and grounds and places were cable's go through holes and rub.
Exceptional understanding of electrical flow.
Great diag and repair Ivan.
Ivan great diag there is not many shops that would have put that much persistent into that problem trying to fix it they would give up or replace module's . That was a great call on the customer to bring it to you . Thanks again for the great videos and information
Great fault-finding technique Ivan.
I think is not a problem of efficiency (like to save time) but more on being persistent, sticking to the plan and a ton of patience. Then maybe you can charge the customer for a block of 2-3 hours or 4-5 hours, etc. As we saw, during the worst moments you moved assertively to the next plan and sticked with it to the end, wrote your results and moved to the next hypothesis... and so on until you declared victory.
Excellent Ivan! That was a nasty problem to track, and you kept your judgement and procedures spot on. Despite the headache these faults are, they are fascinating to follow on screen :-)
Really enjoyed this series...you did a great job in explaining the process from start to finish! Thanks Ivan!
The pixy bloodhound does it again. Another fantastic job Ivan. Thank You.
Yeah that’s happy day for owner. Those trucks are high dollar. So glad you were able to fix it Ivan!
Remarkably clean engine bay
On electrical diagnostic/repair you punch the clock and charge. For a friend well it's up to you. Thanks for the detailed diagnostic.
Oh boy! Those network issues are labour intensive! Only true modern mechnics can find the culprit & fix it😎👏💯
Wow, who'd a thunk it! Nice work as usual Ivan!
Waooo . Excelente my friend..
I like the job you do.
Great Job Ivan! This one was the coolest repair on Can Bus network Thanks for giving Us this incredible learning I wish I could've meet you One day well that would be great day in my life Watching your videos from INDIA!
Hi Ivan, on can network you are going to see 60 ohms even if one of the wire is touching the ground or power. One of the test I usually do is test for 60 ohms an then see if I have continuity with ground. In that case the Can lo was near zero volt on the scope. If you suspected a module and it is in serries in the Can network, you can bypass it with jumpers. Sorry for my bad english!!!! Thanks for your excellente video!
That was amazing, thanks for sharing, those delphi connectors hard to deal with
Good job PH 👍
Since I don't do jobs like Master Ivan does. Yet I do repairs.
I quote by the hour per the book. I'm a DYI mechanic and mostly tackle some jobs.
My brother in law was having issues with his fuel pump shutting off. Then would come back on. I told him. I think we have either a short from the pump to the wiring harness.
If admit I did fire the parts cannon. But we kept the original parts. Installed 2 new parts. I did buy one part for him.
Problem remained.
He took the truck to Ford. They ran a jumper wire to buy pass the pump. They also pulled the bed and cab. They told him the entire harness needs replaced without pin pointing the actual problem.
They broke the harness to the pickup bed. They just used butt connectors and called it good and didn't tell him until I found it.
He was on a trip up North. Truck stalled on the freeway. The jumper wire. All they did was push a bare wire into the harness and it had fallen out. Every 50 or so miles he had to stop and push it back in.
He was so infuriated with the whole screw up. He traded it in. Got a 2020 Chevy and now it's his daily driver.
I would physically connect a 120 ohm resistor across the bus lines to confirm the bus can be terminated properly, then also check the EBCM pins for the presence of the factory termination, and check for shorts to ground / power internally in the EBCM.
CAN bus reminds me of the early days of Ethernet with the 10 base-2 standard, which used the same principle of a multi device bus with terminating resistors and was also a nightmare to diagnose. I wonder why vehicle manufacturers haven't adopted a similar scheme to the rest of the IT industry by moving to a switched or at least hub-based network with dedicated communication lines per device.
Ivan! You are the best mate!
I learned how intermittent wiring problems can be very difficult to fix.
Way to go!!!!! Great job!
Great video Ivan, thanks for the tough diagnosis. Learn so much watching your videos!
The newer can networks can be tricky as some are more fault tolerant than the older single Line networks but with the breakout box it’s quick to test for a short to power or ground but even if you prove that as an issue you still have to locate the problem, splitting the network into separate branches is the best way to go, pulling fuses was smart instead of disconnecting modules, but having scan tools plugged into your dlc can act as another module on your can system for testing. Sometimes you get lucky and find the fault quickly other times you have to keep chipping away at it until you find it, great diag and a great fix.
Witch you need a lift. Like the wizard always preforms a visual inspection of the under side. He would of spotted that in 2 min. Thanks for all your videos Ivan you still a great tech.
Nice work. Thank you for sharing
heads up!!
Pushing pins into sockets can oversize the sockets IF THE TEST PINS ARE TOO LARGE! That's a headache you don't want.
Good JOB .
That daig was a real head banger. That's how new curse words are created...lol Way to stick with it. As always, I learned a few things from this case study. Keep putting out this great content.
Nice job once again Ivan.......Like I've said before, you're a wizard young man. Well done, regards from Spain.
Nice one 👍
Thank you for another well done diagnostic video.
You the man! Great work.
Mindblowing. Even after all this time - it still is.
I blame GM.