2012 VW Jetta No Communication with TCM U0101

This was an awesome video with Paul and Tommy Wolfe from Positive Lead Diagnostics. These are the kind of problems we'll be facing more and more with all the different networks we find in modern cars.
A question for Paul, Tommy or anyone else who likes to chime in. I'd love some more info on the gateway. I mean I know what it is but there was some 'confusion' on the layout here. Is it possible to see a wiring diagram or maybe a 'short' explanation/video to get a more visual interpretation? Kinda miss your smartboard
Oh and I love the DLC breakout box. Was actually looking for one myself before you posted this video. Found the same as yours from AES Wave.

Dylan
My next class at the school will be starting at the beginning of August. I will definitely try to get more info and get some smartboard training involved on this subject. There is so much info out there and when you really get down to it, it is pretty complicated stuff. At least on the engineering side of it. So I need to dumb it down for my mind to "get it" and when I do, you can definitely count on me sharing it with you guys.

ScannerDanner wrote: Dylan
My next class at the school will be starting at the beginning of August. I will definitely try to get more info and get some smartboard training involved on this subject. There is so much info out there and when you really get down to it, it is pretty complicated stuff. At least on the engineering side of it. So I need to dumb it down for my mind to "get it" and when I do, you can definitely count on me sharing it with you guys.

Yep couldn't agree more. This is definitely not something you cover in 1 or 2 videos or lectures. There's a lot of stuff out there on the subject. The basics of CAN bus (high/mid and low speed), MOST, LIN... are not that hard to understand. Troubleshooting it that's a whole different story.
Anyway looking forward to see some more of this in the future. Thx Paul.

Hi guys,


this is excelent OE information on VW CAN systems, explaining fundamental and not so fundamental stuff. for example VW does NOT use two 120 ohm terminating resistors, they use only one 60 ohm resistor and this is located in the ecm.....

www.volkspage.net/technik/ssp/ssp/SSP_269_d1.pdf

www.volkspage.net/technik/ssp/ssp/SSP_238.pdf

Hope you'll enjoy the show

juergen.scholl wrote: Hi guys,


this is excelent OE information on VW CAN systems, explaining fundamental and not so fundamental stuff. for example VW does NOT use two 120 ohm terminating resistors, they use only one 60 ohm resistor and this is located in the ecm.....

www.volkspage.net/technik/ssp/ssp/SSP_269_d1.pdf

www.volkspage.net/technik/ssp/ssp/SSP_238.pdf

Hope you'll enjoy the show

Thanks bro! This looks excellent at first glance.

Thanks for sharing this Juergen! Great info.

Great video and diagnosis.

From what I have learned is that pretty much the core standard of CAN networks used is typically the same for all manufacturers as it was designed by the same guy, Robert Bosch. Although certain network layouts, names etc may vary slightly.

Although not a VW, here is a little diagram from earlier Honda/Acura vehicles with the gateway built into the instrument cluster.
The newer models started using a standalone gateway which basically acts as a translator between different CAN languages. F-CAN may speak "english" where as B-CAN speaks "spanish". Gateway speaks all the languages on the network and can convert messages between all types of CAN which are routed through it.

Cool little fact: Mercedes was the first vehicle to introduce CAN based network on their S-class in 1991.

Hi folks,

although a lot of people ( to whom it may concern....) like bitching about the insane, senseless or difficult way VW/AUDI diagrams are representing electrical circuits, they actually do make sense once you grasp the concept...
And this concept is the actual current flow in the cicuit.

For those who want to learn about it and get comfortable with this kind of diagrams check this out




Not sure if the upload worked.... This is a direct link:

1drv.ms/f/s!Amx3yK-B8rDlg0Z0YavTtPKVNKE9







And if you REALLY want to complain about diagrams check Peugeot out and have a good time.

A few months ago I posted a question about CAN signals on a Ford ABS module 2013 FORD F150 5.OL ABS NO COMM, CAN BUS I eventually fixed the issue but never changed the topic to [FIXED] because I was unsure of what I had done when I fixed it. After watching part 2 and reading a comment from Teardown Dan that it clicked in my head what I had done.

When I had originally looked it the Truck, the connector for the ABS module had obvious signs of damage. And when I had tested all my powers and grounds I thought they were making good contact with the pins on the module. I had originally called a bad module but was then told that it had already been replaced twice before I looked at it.

So I then decided to replace the connector with a dealer part. I purposely only wired in the powers, grounds and CAN lines and left out the sensor wires to see what the results would be. And to my surprise the ABS unit came back on line and all my CAN signals were text book perfect.

It wasn't until I read Teardown Dans comment where he basically says that if from what I understand is that if you have missing powers feeds to some of the module then you can get feedback thru the CAN lines. I don't know if I am correct on what he said but it could make sense on the poor signal from the CAN lines.

Cool, so you're talking about this recent video:



And this comment:


I was having a hard time remembering a user on the forum that goes by "Teardown Dan", lol!

I'm glad that you brought this up, I gotta start reading the YouTube comments.
Thanks Rob!