2012 VW Jetta No Communication with TCM U0101 (part 2)

[@teardowndan5364]

Typical IO pins have protection diodes that clamp the IO lines to an internal power supply rail. If input power is missing, data lines get clamped to that rail (which will be somewhere near 0V due to not being powered up) and that's where you get the signal distortion from. Under normal operation, the internal supply rail would be at something like 5V, which is higher than CAN bus voltages and would reverse-bias the diodes, taking them (and the distortion they caused while the TCM was powered down) out of the equation.

[@ScannerDanner]

Everyone paying attention? You should be! This is the kind of "internal network" stuff I was talking about, that we all need to learn. Not the typical explanations of a network that everyone reads from a book.

[@teardowndan5364]

The typical explanation assumes that the circuitry handling said communications is properly powered up :) (Just like everyone assumed that when Tom said he had already checked power and ground, he had actually checked all applicable power and ground :) )

[@BBS_Robski]

ScannerDanner i was the first to reply in the previous vid with an explanation of the BUS & testing etc but it was blatantly ignored (replies after got thumbed up/love hearted) so i deleted it, i won't waste my time in future because if there's one thing i hate is ignorance 😖

[@sandyande]

tell me sir I'm listening would love to learn more cheers sandy

[@BBS_Robski]

sandy anderson read the SSP that a link was supplied for pal in the first vid !

[@OneAuto]

In my opinion there was no mistake by Tom.. He left that day, went to bed with it on his mind, woke up with it on his mind, came in the next day and friggin NAILED IT! Well done sir! I've done similar in the past when the customer has given me the time to thoroughly investigate the fault. I think mistakes are made from pressures of a busy workshop environment or a non understanding customer screaming for their car to be fixed. Again great job guys.

[@roadkill5333]

He didn't own a mistake, he saved the day!! He made sure that he checked every possible probability, before replacing the module!! That shows two distinct facts!! He had an awesome teacher, and he learned! How did the fuse get moved?? Well, most likely the operator of the vehicle, or a known person of the operator!! They blew a fuse, and checked and misplaced the TCM fuse, or they were playing technician, and had no business in there, and put it in the wrong slot. Either way, the cost was a tow bill, and a large diagnostic fee! $$$ GREAT VIDEO!!! And learning experience! Good job, to you both!

[@teardowndan5364]

The most important lesson here: don't trust that the tech who was there first and told you that he tested power and ground actually tested *ALL* power and ground! That is the first thing you need to make 100% certain you tested before delving any deeper into electronic troubleshooting.

[@ScannerDanner]

Of course! If you knew me better, I never trust another guys work, but Tommy is one of the few people in my life that I absolutely do. I still should have checked and would have if I was the one making the call on the TCM. I would have had to see it first hand, even if my own brother told me they were good. This situation was different.

[@billyr9840]

Come on lets be fair to Tommy, that factory wiring diagram is about the worst engineered document on the planet that he was using and you have to give him a lot of credit because his gut feeling/instincts told him to check and re-check his work before he replaced a 1,000 dollar TCM ! I'd say the man did pretty well in that respect !

[@teardowndan5364]

Yes, those schematics looked pretty useless, doesn't change the fact that you should check for additional power feeds when you know they are commonplace in that application. As for his 'gut feeling', anyone would be nervous about replacing a $1000 component when the unnecessary expense comes out of their own pocket if they do the honest thing and don't charge the customer for an incorrect diagnostic and the alternative is hoping the customer doesn't sue you for fraud if you attempt to pass the cost of your mistake along.

[@scientist100]

@@NorthernCorruptionMonitor907 El chapo Audits wtf is this lol? Chapo is done man.

[@northpostman]

Great job Tommy, don't listen to the trolls. I've been a tech. for over 30 years and have had my share of butt kickings from tough repairs. Nothing wrong with re-checking, and nothing wrong with having missed that fuse on the first go round. The important thing is you found it, didn't replace the TCM, and learned along the way. That's what makes a great technician. The people that always criticize and never make mistakes are the ones that don't do anything.

[@PositiveLeadDiagnostics]

thank you!! I honestly can say I'm glad I missed it, you learn from experience and you retain information better when you have it hands on

[@billyr9840]

Your right about trolls but think about it why would he check the fuses before scoping the network because he was getting a no com ? And why would he check the fuses because he thought he had all his powers and grounds at the TCM ? The only error he made was, he understandably over looked a additional power supply. Being a good technician he double checked his work and found his over sight ! So I ask anybody that is criticizing him, what's wrong with that ?

[@DormantIdeasNIQ]

@@billyr9840 @all of you... nothing wrong with missing it... just that I have seen many of Danner's videos and caught him more than once not being transparent... I am not the only person who noticed he missed it, only trying to keep him honest and admit he did, that is all. Don't be so defensive... this will only make Danner better... he is good already.

[@pskauto6798]

I wrote this comment like 5 times because it got long , sincere , defensive , educational.. This video is great because it shows how diligently he was working to find the true cost of this customers problem so their money didn't get spent poorly. We all make mistakes, doesn't matter how many years you've been in the field or how many patches are on your arm , or how big your tool box is . But how many people are willing to post those mistakes to the Internet for thousands of people to see? There is a great lesson to be learned here and I'm glad that I got to watch this video

[@ScannerDanner]

Thanks Mikey! It is difficult at times to hear about the mistake you made over and over and over again but I'm okay with it because the end result is better for someone learning. BTW, you should hang out with us tonight for the Pens game. Tommy is coming over. Game is at 8

[@pskauto6798]

ScannerDanner ill shoot you a text later on if I can stop by brother , thanks for the invite !

[@MD-173]

Tommy's intuition was spot on! Your gut said check again, don't just fire a module at it. This was a win for for you and a BIG win for the customer! Always listen to your gut kid!

[@PineHollowAutoDiagnostics]

Wow great save! "But you should just check the fuses to begin with! You're overthinking it!" Let's just say it's not the blown fuses that are hard to find. It's the MISSING ones, or in your case even more bizarre misplaced fuse? Great job!!

[@ScannerDanner]

Thanks Ivan! Great to hear from you

[@timowallin8020]

Yeah i have seen owners books (Ford Fiesta) that says "Not In Use" on needed fuse on them. So, even original source are some times big ? mark to me. When you are missing power from part and aren't sure your fuse holder diagram is update and you come to find out that your fuse has grown legs its almost always a mystery who took it out to walk and why? ;)

[@stefanczechorskidds8435]

A quick check of ALL the fuses would have made this one stand out as that space is suppose to be vacant and it would have tested "open"! The way these networks and systems all communicate with one another, any one fuse could affect other components. Great vid, but you really got blind sided!

[@nicknicu1787]

No wonder the man's name is Wolf! You don't trick a wolf easily. You didn't make a mistake Tom,the 1000 bucks are still in the customer's pockets! Great job guys!

[@PicassoPete]

Never take anyone’s word that they’ve checked everything... real head scratcher hey. We viewers are so grateful for all these video’s. They all add to our knowledge. Many thanks. Peter A.

[@ScannerDanner]

A quick thank you to whoever just translated the closed caption in Polish! There is a review period where others that speak your language review it and it becomes live after a few weeks. I could unlock it now but you could have typed anything and I wouldn't know. If we know each other and have talked before, that's different. Either way thank you!

[@RJ-ds6zo]

You did a good job! You are not a part changer! This video shows that is not always easy to find the fault, and it shows that you have to reconsider your conclusion many times. I guess you got a happy customer!

[@omen376]

Thank for taking the time to make this video. I know about 7 years have passed, but watching you go back to the basics motivated me to do the same. I went back and also found that one of the fuses aas MISSING! I wouldn't have even given going back a chance, but this video guided me down the correct path. Thanks man.

[@turningwrenchesautorepairm5017]

Anyone who has been diagnosing for while has made many mistakes. I check and double check all my work. Even then I have slipped up. I am glad you men posted the REAL fix. You just affirmed the most important tests that must be made when doing electrical diagnoses... POWER AND GROUNDS. great stuff !!

[@haywardsautomotive6156]

Great respect for Tommy owning that and easy to do with those WDs and Mitchell are definitely easier to read. That power from the fuse was affecting the oscillator which is why the CAN signal was unreadable by other network nodes and it shouldn't affect the network resistance. I don't mess with VWs and unfamiliar with their CAN but after a little research b/c I'm bored to death with no cars today it appears there is only one terminating resistor & it's located in the ECM & is a 60 ohm resistor. Powers & grounds so important and again to Tommy hopefully you see this...I respect you so much more now b/c we all make mistakes and with my 40+ years I'm chuckling right now thinking of some of mine but it takes integrity to admitting a mistake but the bottom line was you backtracked & found the problem and prevented a $1K mistake...great job. For you Paul you produced an extremely talented & knowledgeable tech & it's great to see you guys working together. Both of you keep the videos coming b/c they are great and I hardly watch TV anymore!!

[@SmittySmithsonite]

Same here! Thinking about cancelling my Dish Network subscription. :D

[@andreasmaltcke117]

"WDs and Mitchell are definitely easier to read" - I agree. VW diagrams (and many other european brands) ... no comments. The diagrams are unreadable. Useful but extremely unreadable. Car installation scheme (general, no details) for 80-100 pages? This is a joke! Especially that there are only "modules" on it, not integrated circuits and passive components. Bad joke. This type of CAN bus probably (!) does not have a classical termination resistor, but some kind of "resistance simulator" (semiconductor, built into a transmitter / receiver integrated circuit). Regardless of that, any measure of resistance to the system connected to the power is pointless because the results are bad/random. The meters we use (universal multimeters) are not suitable for such measurements.

[@tubetime39]

@@SmittySmithsonite smiling here. I am old and have no idea how car electronics work but was forced to try and learn bc of buying a used vehicle that went south..blah blah, But wanting to learn for years & having to repair my vehicle myself, ($$) I am here on my computer next to my tv, which is off. Like you, this is more entertaining, plus useful & $$ saving. My head is swimming but so far this is fun. Like when I put my first clutch in '53 Merc at 16 y o.

[@SmittySmithsonite]

@@tubetime39 AMEN, brother!

[@gouveiaclassicos]

Well done that’s the real difference between a technician and a parts changer Top Information Top Videos

[@JMUBrew]

I was struggling with the same no TCM comms for a couple hours until I watched this video. As soon as you started describing the fuse box and how there would be terminals on both bottom/top for the fuse and that someone had put it in the wrong spot, one over, I realized what I had screwed up the day before. Ran out to my car, swapped the fuse locations, fired it up and bingo - Transmission was back and all my lights cleared out after a quick drive. Thank you!

[@ddk80]

Can you tell me the symptoms you were having? Was it difficult to shift out of park?

[@sdlawyer6735]

Granted this is 5 years later, but you can get that exact TCM for $30.00 now. Thanks for the great video!

[@christophermanley653]

love how humble and patient this guy is. Damn good Job!!!

[@SmittySmithsonite]

After watching this one, I'm using a paint pen any time I remove fuses on these ones with missing spaces in the box. I'll forget where the fuse goes, and cause myself one big headache! :D Excellent vid! Looking forward to the upcoming CAN network vids - one year ago, I didn't have the slightest clue what CAN was, nor how it worked. THANKS again! :)

[@edwardthayer9386]

Dude didn't miss anything! If he would have replaced the TCM then you would have missed it! You actually nailed it!👑👍

[@nandor690]

Part 2 took a hard left turn didn't it. I was wondering how that would cause distortion. But the pinned explanation seems to explain it perfectly. Now I know!!!!! Thanks guys!

[@MiracleMAX]

Hey Tommy, we have all been there, brother! Nothing worse than someone else having a play with the vehicle, thinking they can fix it without having a clue about how to diagnose the system. Glad you shared it with us. We all miss things, but it is really important to share it with fellow Techs, so that we can all learn from one another's mistakes as well as our successes.

[@markbraksator8162]

For everyone who has 2010 Jetta 2.5L: The fuse table in the manual doesn't describe this extra 20amp fuse and not having this fuse in slot #30 on the diagram is exactly the cause of the issue described in this video. This is a pretty bad omission in the car manual. Anyway, watching this video, helped me get my car unstack from park. Thanks!

[@KStewart-th4sk]

Doesn't explain that the car WAS working at some point---fuse had to be in the proper place then.

[@galloi]

Thank you very much. I had the same thing happen to one of my customers car. I was about to get a new TCM when i came across this video. I really appreciate guys like you.

[@docfeelgood111]

Thanks for sharing! Great job Tommy for catching the misplaced fuse, it doesn't matter you missed it the first time. The main thing is you did the smart thing and rechecked your work before condemning the module! They should call automotive repair shops a practice like they do doctor office because as technicians we're always learning and evolving our tecniques with the always changing technology.

[@prmayner]

when i retire which is coming up shortly, i want tommy working on my vehicle. great job tom.

[@davesdrone3125]

My Mercedes has multiple CAN networks which are all connected to the central gateway. I've been having a crank, no start issue and no codes to help... Your videos have been super useful and I just bought your book to help brings into perspective. Hopefully I find the issue soon!

[@baxrok2.]

In one of his videos where he talked about why he loved his first gen power probe, The Humble Mechanic said that the first thing he does on cars that come in with weird problems is quickly check every fuse in the fuse boxes. Only takes a minute he said. I thought that was kind of a waste of time. After seeing this, I can see how that might not be a bad first step. Epic job guys. Lots of valuable CAN and module lessons here. Thanks!

[@PositiveLeadDiagnostics]

thanks for watching, everyone says just check the fuse first but that method would not have helped, that fuse would have had power on it due to the fusebox design, only knowing actual fuse location was the fix.

[@baxrok2.]

Got it. Killer job as always Tom. Thanks for sharing this video with us and most of all for educating us on the importance of perseverance and a thorough and complete diagnosis!

[@kerrygleeson4409]

Well done yes I have done the same thing woking on can bus systems After 40 years working on truck and cars you always learn something new Again great job

[@wgrillo]

The absolute best diagnostic can video that I’ve seen. Made everything easy to understand. The thing that raised an eyebrow with me is when tommy said there was only one power to the Tcm but I blew that off because of their level of expertise being light years ahead of myself . Just goes to show how the best can over look something and Dan was correct about the complex nature of wiring diagrams and which format that you use to read them. I’m currently working on a 2006 dodge ram with a Cummins diesel that starts and runs fine but has no comm to the pcm. My diagnosis was a bad pcm however before I pull the chain on a new one I’m going to go back and use what I’ve learned in this video to recheck my work. Thanks and great job fellas 😃😃😃

[@davedunington7637]

We are never done learning.... This new technology is a lot of learning... Thank YOU.. I , for one appreciate it....

[@GoTechTraining]

Great video Paul and Tommy. Great lesson. We can all learn from this, just like Tommy did.

[@ScannerDanner]

Thanks guys! Keep up the great work yourselves

[@GRUSSNewton]

Half of the battle with modern vehicles is access to decent wiring diagrams, there's that much on the vehicle that even when using 'official manufacturer' ones, the diagrams are always split up. I had a similar situation with a Vauxhall Astra J. Rear wiper not working. Previous tech had condemned the BCM after checking fuses etc. Going back over the online diagrams revealed another fuse which was a unnamed power into the BCM.... On a totally separate diagram. The fuse was missing (just like this actually..) Replaced the fuse and the wiper worked! Enjoyed the video!

[@blockbertus]

Great job and videos, guys. Well done. I find it interesting, that Tommy sounds (voice wise) almost the same as +ScannerDanner :)

[@jeffhesse8415]

Nice. It's always good to double, triple check. I keep telling my boss- I need good information to properly diagnose electrical problems. No mistake, you fixed without replacing the wrong part. Good job.

[@edgundlach2811]

it's not really a mistake until the wrong part is put in! may consider it an oversight at most. Great job diagnosing!

[@tdracing13]

Great video guys! No reason to beat yourself up, that's why we double and triple check ourselves. I've found that man made problems are way harder to find than typical failures.

[@Gmansour1971]

Mistake made, but not really, the controller was never ordered nor installed. The customer never took the car, so the correction overcame the mistake. I Love Mistakes like that. Great job Tommy. Dan you are the man.

[@shawns442]

Awesome Technician Skills (Not Mechanic) Tommy! 99% of shops probably would have made wrong call. Sometimes the simplest stuff like that fuse can cost a Tech 8 or more hours of troubleshooting time which most shops won't bill customer. I have been Tech for 40 years. When cars like this one eat a Techs lunch, customers need to pay. Hope you recovered your time. Great Video and your skills are awesome!

[@GSRThree]

shawns442 I do mobile vehicle for a living and shops make a bad call on module's about 15% of the time and I is usually something simple they missed. I have a Facebook page MVP Programming I have recently started. You should check it out for my tip of the week please like and share.

[@BuggysTowJam]

@@GSRThree would you consider integrating your knowledge into your yt channel? I'm going to sub your channel in hopes you do. I'm old school and don't use fb. I know the rest of the world does and it me not be worth your time to bring your message to yt. But if you do I'll be there to learn from you.

[@KStewart-th4sk]

+shawns442 I don't necessarily agree that the customer should pay. I don't think many techs get enough training in an industry that is changing so fast. Don't think a customer should be on the hook for that. This guy owned up to his mistake and kind of sounds like the OEM schematics suck compared to the ones Scanner Danner looked at later. Strange! I think the worst problem for a tech to find is an intermittent problem. I would hate to be the customer or tech in that situation.

[@steveguest8028]

Great fix guys,this one was a real head scratcher lol and all because of a miss placed fuse,thing is if you explained to your customer(after spending several hours diagnostics)that the cause was just this fuse issue they simply wouldn’t understand why the bill was so expensive....very difficult situation that I myself have found myself in a fair few times in the past.....Many Thanks

[@HOTRODRICO]

amazing work Tom... you are quite the logical detective... and if you were evil you could have taxed the hell outta the poor owner.. but since you are a real person and one hell of a tech, you solved a huge issue with a simple solution.. props to you bro.. you had a great teacher (and i learned a lot) thanks

[@ScottPuopolo]

You checked some of the powers and grounds initially, the TCM was probably partially energized and not operating correctly so the network comms were corrupted. After getting all proper power, TCM was working 100%, comms restored. Just my hunch. Great vids and great to see the thought process.

[@teardowndan5364]

In the first video, I called no power to whatever circuitry was responsible for driving the CAN bus pins. Since Tom said he already checked power at the module though, I was thinking blown internal fuse or supply regulator. I doubt many people would think of checking for multiple external 12V power feeds from the same source but different fuses up-front.

[@ScannerDanner]

That's actually common in our field Dan. Having 2 to 3 main powers, an ignition power and multiple grounds

[@PositiveLeadDiagnostics]

I went over that diagram initially when I was doing the first power and ground check, and I know almost every module has more than 1 power feed, I honestly just missed it. Teardown Dan did call that..

[@robertwhitworth7346]

I am gonna say I nearly bailed on this video, SO glad a stuck with it, interesting to see the teacher let the student take the lead. I can image drinking a beer after figuring this one out. Great job!

[@codybear56]

You said you checked the powers and grounds. That was a false statement in the first segment. Verdict says you intentionally withheld information, or you made a mistake(for all of the people saying its not a mistake). You could have fixed it hours earlier than you did. Or you could have replaced the TCM and fixed it hours later. But we simply can't judge a mistake on it prospective outcomes either. A mistake is just a mistake. All of your tests were valid at the end of the day and you fixed it. So good job with that. I chased a stupid brake light signal all the way up to a relay in the wrong slot once. I don't want to admit how long it took. But I fixed it.

[@99rattle]

Always nice have fuse layout to help, with location of unit fuse. Finding recently similar issues like u just experienced, fuse in wrong location or missing. Pixxies been in there an moved them around , no one touched it before, customer says it just up an quit & towed to ur garage .. :) Nice to see u had sense to recheck ur work.. Good Job

[@chriskatanic8080]

Great find. I know how it feels to make a call on an expensive part and not have it fix the problem. It took me a while to teach myself how to read VW wiring diagrams, and I still despise them!

[@PositiveLeadDiagnostics]

they are awful, and they keep getting worse because they're adding more modules into the car

[@volvo09]

wow! I wonder what would have caused someone to be in there in the first place, odd find but holy crap... good work on not ignoring checks that weren't adding up! he's gained a new subscriber here.

[@alangaudry724]

I work out at Cape Canaveral Space Force center. Great two part video. Make yourself a check list just like a aircraft pilot uses . I call it Toadisim my word for when somebody else has been there and screwed it up. I hope you put more videos up

[@milanmilan1740]

I was working for many years on Caterpilar.They have solution for testing ECM.You get new ECM and program it and turn on testing .Install ECM and if that fixes problem You are done.If not remove new ECM and in 24 hours it clear it self and You could return it.Very good feature.If you leave it in vehicle more than 24 hours test mode go off and you bought ECM.

[@TTRVision]

.... imho we are dealing with some complicate systems and sometimes we forgot to start with the fuses. when attacking a problem like this we don`t have in mind a "simple solution" for the problem like a fuse. this is related also to the fact that we don`t find often blown fuses that are solving our "hunting" problems and we are always testing and testing to find and solve :) ... big thanks to you Guys , best regards from Europe. maybe you don`t have all the info about european cars but you have the best (by far) professional approach and skills to deal with and solve the issues. but , above all this , sharing the information is the most important thing. full respect and infinite thanks for that. Paul`s book and his channel`s are more than a gold mine !

[@ScannerDanner]

Thanks so much! Crazy thing on this one is even if we tested the fuses using the conventional way, it would have tested good! Only fuse removal and inspection revealed the missing pin and wrong location lol. In other words, I almost never remove a fuse to test them and I would have missed it using the typical way that I test them. But you are correct, in the real world, it's almost never the fuse anyway and starting there is not the typical first approach to a seasoned tech. Thanks for the comment and kind words about ScannerDanner Premium

[@edwardthayer9386]

I really appreciate the honesty and rawness of the video! THANK YOU!👑

[@exmotorsports]

Hey Tom..Always good to measure 3 times and cut once if that's what it takes..besides, I can see how it can be so easily overlooked with a piss poor diagram like that..Paul said it right.."THEY SUCK.!" Another thing good to remember is to ask LOTS of questions from the customer..Maybe some light could have shined on it. Bet this is one you'll remember for a long time..I know I can remember all of mine. The learning curve bro. We all make them. Just happy to you win on this one. Thanks for sharing it with us. Cheers to you both.

[@PositiveLeadDiagnostics]

absolutely!! we kept on measuring...the same question what is a full proof test to call this module? are there any other checks we can do? idk if we would have gotten this info from the customer, for some reason they don't like to give us important info lol

[@thedreadedgman]

Danner's trick of highlighting the legs of the circuit on the wiring diagram in different colour highlighter pens is good especially with those multi-page abominations

[@stigonutube]

wow, that was a close call however all good and good outcome for the customer in the end. im no expert diy but when i saw those odd waveforms i was 100% with you guys on diagnosis of tcm, cars are tricky beasts. slap for VW for tcm placement grrr..

[@ianmcdermott8951]

Good job Tommy, started following this channel as i follow SD, I am an Audi tech and have to admit that elsawin current flow diagrams are not the best if not using them daily, also with the dealer computer odis test plan it would have pointed you to check that fuse at the start, but in the end you got there. those picoscopes are well more advanced than the Audi scope we use by the way. Looking forward to watching more videos bud.

[@guayaco-dm3vu]

Thanks Paul and Tom... Always learning something new from you guys.. Keep them videos coming Hermanos,You guys are helping us set better standards for us and future techs...

[@alangaudry724]

P.S I work on company owned fleet vehicles. Workers are borrowing/moving fuses to replace blown fuses on power outlets to charge thier phones. Phycology if people ( toads)(toadisim) is a must . love the Videos

[@AutoScopeTech]

always ask yourself if i replace x part and it doesnt fix the truck what would i check ? then check it

[@billyr9840]

That is awesome advise !

[@jesseruiz2337]

good job Wolff, I'm sure it can be intimidating with SD in the house but u retract ur steps 1 last time n nailed it dude, rite on!!!

[@MrBugzzie]

Wow !!! That is amazing how such a simple item is as important as a more complicated module

[@pinpointautomotiverepair1592]

It's very easy to miss something like this, great job Tommy for being thorough!

[@haywardsautomotive6156]

Couldn't agree more and he went back and double checked himself before he condemned the TCM and found the missing power.

[@PositiveLeadDiagnostics]

thanks guys! there should be a way to prove the module is bad, if you cant prove it...back to basics

[@wysetech2000]

Excellent job by both of you. Have seen missing/misplaced fuses causing problems before. I hate German car schematics too but i'm sure if you work with them enough you get used to them. I question my diagnostics all the time and check and recheck and sometimes i'm wrong. A $1000 mistake would be a kick in the butt. It's all about learning and persistence in our trade and it will never end.

[@jacoponono8179]

What I want to know, was what did the customer say after the Tommy fixed the car and they questioned him (and explained the moved fuse) "Hey man, did you know your car wouldn't shift because you had a fuse in the wrong spot?" now that would be funny to film... On another note, one of my favorite things about watching scannerdanner videos is about how he is humble with the learning process. I really think the mistakes are great for filming and teaching moments. It takes a lot of courage to be honest about your mistakes.

[@ricciamonsterhigh836]

now i have dtc u0101 in a seat ibiza 2013 dsg, the first is searching info.in the internet , first appear your video is great work thank you for share

[@juanvelasco4607]

that was a very good trouble shooting trying to find the problem and I pay very good attention to all methods to go to the end, my own opinion is I should of start by checking the shifter wiring. I learn a lot more the methods you used in this video about how the system works. 👍👍👍

[@rodx5571]

I like the fact that he double checked himself, and admitted he made a mistake BEFORE replacing the module. The flip side of the 1000$ module is, if you buy Euro, bring your wallet, you should expect to pay. People buy cars they can barely afford the payments and certainly cant afford to fix. Can afford to buy it, but not to own it. Great vid as usual.

[@petetown13]

Almost 2 hours of video on can networks to realize you didn't check the most basic of things, a fuse. I wouldn't have uploaded this video if I were you, but I'm about to address the same thing with a jetta so good info for me to know

[@ScannerDanner]

😂 we learned a lot along the way and shared our learning process (ill be it the hard way) with everyone. I'm not ashamed. It was real.

[@motorcyclesandridingfree2899]

Hey everyone misses stuff at times you did it right and rechecked the wiring diagram and found it. At least you admit and learned from the mistake and you didn't give up and throw a module at it.

[@PositiveLeadDiagnostics]

you are correct, everyone misses something. but that's the troubleshooting experience and we all learn from it

[@ssautomotiverepair673]

It's the humbling experiences that make us better.

[@Airman..]

Dude you are a lighthouse in diagnostics business

[@waynemontgomery8484]

great video guys, im' a marine tech and i see this kind of thing a lot . Customers try to fix then wont tell what they did. add salt water and air .

[@mohamedrahib7685]

thanks Mr scanner danner .god bless you ,I learn a lot of new ideas from your videos

[@train-addict4656]

Good job , I was concerned there was only one power feed . And your right we keep checking over and over , 1000 dollar TCM .

[@TrevorReaStewartnexus]

Way to go Tommy!! I'm a 3rd year working at a dealer up in Canada. Love this video man! Good Job!

[@PositiveLeadDiagnostics]

thanks Trevor!!!

[@fredflintstone8048]

Great job guys! My guess on the distortion on the network may be the way the module will handle the termination of the CAN internally with vs. without the proper power (active circuitry vs. passive components like a fixed resistor etc). CAN is an RF signal network that is sensitive to the components on the bus. With a module that is not receiving the proper power there is no accounting for what the CAN network is being exposed to connection wise. I've not dug into the termination circuits of VW CAN bus modules so this is merely an educated guess based on knowledge of other computer com networks that have a device that's connected to the bus exposing the entire bus to circumstances that distort the signals. Again fantastic job Tommy, and Dan. Thanks for sharing, and reminding us to dig in and check everything carefully.

[@ScannerDanner]

It Paul but that okay brother, I get Dan a lot. Thanks for you input!

[@fredflintstone8048]

Sorry for the brain fart. I know you're Paul... (facepalm).. Love your work.

[@PositiveLeadDiagnostics]

I'm calling him Dan from now on lol

[@eloverz]

much appreciation for the fundamental check steps that you did guys.. its interesting for me to know even though the problem was solved, what would've the resistance difference be with the TCM connected and not after knowing the power line is ok, like how major the difference would be.. im sure it wont be at the approved spec so from there the next step is to check the wiring following i guess revealing the missing power feed. other than that it sure was a good learning experience, thanks for both of you.

[@How2Wrench]

AWESOME !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Love you being authentic!

[@chriscanty8214]

man you are a awesome tech with a awesome teacher keep it up

[@jackfoster8319]

LOVE rubbin in the mud of communication! You guys attacked with what you had.

[@jaycharles1890]

Only thing I can think the resistance check would be good for is when TCM is unplugged and you check resistance from another location on the network and it is say 60 ohms and then when you connect the TCM back up It would say jump to above 70 ohms with a faulty TCM. Don't know if that would be the case but I would think so. Still loving and following your work from Scotland. stay good buddy

[@JAIVS26]

that's why everyone hates vw wiring diagrams .. i just went to my OD5 and see the fuse 30 next to the fuse 2 and fuse 14 .. good thing you found the problem!

[@DanWallis86]

Probably one of my favourite SD diags. Awesome find Tommy. 👍

[@InsideOfMyOwnMind]

All you guys who are fighting can nets would benefit from studying up on transmission line theory, standing (reflected) waves, termination, etc. If that TCM had active internal termination that would point blank explain the distorted bit stream due to no power at the TCM. Everything that hits the TCM bounces back into the network mixing with valid data instead of being "absorbed" by the termination in the module. In IT they use a thing called a time domain reflectometer (TDR). This device will tell you not only if you have an open or shorted line or connected component (module) but it will also tell you where on the line the defect is. Even if it's not practical to use one of these in automotive knowing how they work and what they are looking for will lift veils from the troubleshooting process.

[@PositiveLeadDiagnostics]

so the distortion was actually the signal not being absorbed and bouncing back into the can line? pretty cool I'm going to look into that, thanks

[@billyr9840]

Wow, just did a little research on that TDR thingy and that is awesome ! So much to learn !

[@mmichaeldonavon]

I used a TDR many times! Been a 100 years ago. :) I always used the TDR on coax cabling. (on the C-141B airplanes. They are now, all of them, in the "bone yard." Trying to think if a TDR would work on a twisted (shielded pair). Think so, do the shielding of the wiring pair being there. Doesn't work on a "single" wire - must have the shielding (as a conductor).

[@chrismechanic2000]

i had a jaguar tdi crank but non start to diagnose, no comm, i found the maf wiring was shorting out on a metal pipe bolted to the engine so for a while i thought the ecu was blown as it is common for the ecu's to go wrong on this model, i didnt have a wire diagram but i did check for power and grounds, no live feed to the engine ecu. it turned out to be a bad relay in the engine fuse/relay box. its like the old measure twice cut once rule, good vids keep em coming.

[@66crush9]

Perhaps someone checking the TCM fuse to see if it was bad then plugging it back in the wrong location, but that only would make sense if the TCM was suspect before this set of symptoms occcured... great video!

[@kd1s]

What you've learned has been present in the I.T. and engineering world forever. I like to call it the 11th Commandment - always check they power. Always!

[@ScannerDanner]

Absolutely!

[@ozzstars_cars]

That was some serious real life diagnostics! Nice job

[@martinrubenstein7943]

Excellent follow-up to Part 1, Paul and Tommy. What a valuable lesson for everyone: how a less-than-satisfactory wiring diagram could have cost you $1k, let alone the hurt to your pride. Paul, Tommy, you make a great team; how about a rematch?

[@ScannerDanner]

Glad you enjoyed it and thank you for your comment on Part 1 too. Not many saw it the way you did. I certainly thought so when we produced it! But you are right, I have learned a lot since this video! For one, when pins 6 and 14 are not wired directly into the CAN network but extend ONLY to a gateway module, you will not see the resistance you are looking for (120) and I've also learned that there is no standard in that regard lol Thanks for the support on SD Premium too. It really means a lot. Watch my 2018 Duramax series when you have time. It is an intermittent CAN "crash"

[@martinrubenstein7943]

@@ScannerDanner Thanks, Paul, for explaining why tapping into Pins 6 and 14 will not give any useful results on some cars. That’s a bit of info I’m definitely going to add as a hand-written note to your book. And as for having time to watch one of your videos, that’s something I’ve always got time for.

[@ScannerDanner]

@@martinrubenstein7943 thanks again Martin!

[@TheCarTakerGarage]

Wow..this was awesome!Great save.To be fair..it would be one of the first things i would check personally(all powerfeeds/fuses),but it is indeed super easy to overlook anything to be honest.So this video is just fantastic..and great job,and great words on "Always double check" previous checks/work you performed.Greeeeetings from Norway,Stefan :)

[@markferraro5250]

great 2 part series SD wow it teaches so many to avoid that rabbit hole i totally agree with you about the track wiring vs Mitchell motologic re write wiring diagrams

[@angrystrong0591]

Thanks!

[@ScannerDanner]

Jeffrey, thank you so much. I don't get these often, this may be just the second one. I really appreciate this. Thank you!

[@abbsgarage.9676]

Dude mad respect any one can miss something but not everyone damit it... honesty it's what's up @positivelead.

[@aissaaneslyes3566]

as "car doctor" may be you have to ask the customer what happened and if he had touch any thing and the second thing why VW did not put one single fuse for the can bus and how much cost this hours of labor for misplaced fuse , thanx for the vdo i learned a lot of things , my respect

[@mikesaldana3760]

keep going man your getting better every day

[@sillybellyfriendsramirez6360]

good job man because of your video I found my problem abs no comunication fuse #49

[@ScannerDanner]

sweet!

[@adrianlowes1848]

As a tech that primarily works on euro cars the vw diagrams are actually not that bad, yes you have to look at a few pages but they are ok. Most euro control modules have more than 1 power i.e term 15 as Tommy mentioned and term 30. Fair play to the guy for owning an initial mis diag we have all done it

[@somerandomguy3868]

good call very good call

[@josealers67]

Premium channel is excellent. Highly recommended. Thanks again.

[@ScannerDanner]

Thanks Jose!

[@darrenflounders2803]

jose alers did the Mitchell wiring diagram show the fuse a pose to the Orem diagrams

[@darrenflounders2803]

ScannerDanner good lesson learnt but am wondering did Mitchell diagram show this fuse ?

[@movingforward4950]

I will have to go back over 1 and 2 again I believe my 2002 Audi TT is having a similar issue no communication it does run there's a fault with the ABS I've learned a few things to experiment with thanks again

[@LG20626]

oh em gee 90k subscribers, you are gonna get a play button soon!! That's awesome, you deserve it! ~WendyG

[@leebarnes655]

Interesting clue as to who it could have been that misplaced the fuse is that fact that SC28 is entirely missing. This one powers the radio and the navigation display unit. I suspect the owner took his stereo out to resell it or the car and really isn't qualified to be doing that level of work. Had to have it towed from his garage and other prices to be determined, I'm thinking this is his last time in a fuse box. Nice one Tommy, we've all done it and much, much worse too. But then we didn't put in on youtube either - hee hee.

[@ScannerDanner]

Exactly