CAN Generation VW Golfs pre-2003 vs. post-2003

Hello everyone,

Here's a short introduction: My name is Lukas, I'm 33 years old, and I have a son and a wife. We live in the beautiful city of Wiesbaden.
I work for an automotive supplier, and my main responsibility is to equip vehicles with measurement technology and to conduct vehicle tests accordingly.
Therefore, I also have access to software like Peakcan or Cancase Xl, among others.

'For over 10 years, I've been privately involved in various vehicle and engine modifications, and I've now registered here because of my current project.'

It's a Touran (year 2004).

• Base
o 100kW TDI engine.
ESP MK60 FWD
• Renovation
o 1.8t BAM engine from Audi S3 (year 2003)
o ESP MK60 AWD
o 4-Motion Gen 3 (Passat 3C 3.2L)


As most people should know, the problem arises precisely now, with the different generations of CAN Bus systems. Currently, I haven't modified the ESP unit yet, so it's still the original Touran version.
The following problems have now emerged:

While I can read all the data using VCDS, it stops after a few minutes due to a communication problem with the ESP control unit. The question now is whether it's solely related to the ESP (Electronic Stability Program) or if it's a more fundamental CAN (Controller Area Network) problem?

I have now found out which other engine uses a similar ME7 control unit (like the BAM) and should have the newer CAN bus system. I found that the BFB engine, used in the A4 B7 (from the year 2007 onwards), fits the bill.

Now, the crucial question: Can I 'code' my 'old' BAM engine control unit to the new CAN bus, or am I mistaken in my assumptions?


Next question:
Since the GRA (Gearbox Reference Angle) in the Touran is controlled by the steering column control unit, which is not present in the Audi S3, the GRA will not function.
The logic of the switches is the same, but in the S3 (BAM), the (5) cables go directly to the M-module, while in the Touran, only one cable from the steering column control unit goes to the M-module.

For the A4 (year 2007), it should work similarly to the Touran. I suspect that it can be done, as the A4's control unit is very similar to the S3's.



I would be happy if I could continue here .

Hello Lukas,

The CAN bus drive system is the same, but the control units now communicate with each other using different message IDs, or these messages are structured differently.
If only individual messages arrive on different IDs, or if something else is different, it might be possible to adjust it with the appropriate hardware.

The transport protocol (TP2.0 or TP1.6) may have been modified. The transport protocol describes how a communication channel functions between two control units. If there are any changes here, you realistically have no chance.

To be honest, I don't know anyone who has managed to do the former just for fun. It's certainly feasible if you can manage it yourself, but generally, people who achieve that level of success already earn enough money to simply buy the vehicle they want.

The easiest way is to simply obtain the appropriate engines/control units from the same or a similar vehicle with a different engine configuration.

In my experience, converting from diesel to gasoline usually never pays off. "There are simply too many parts missing, or they are different."

Quote:

Now, the crucial question: can I "code" my "old" BAM engine control unit onto the new CAN bus

?
No.

Quote:

or am I mistaken about that?

Yes.


Best regards, Rainer.

Hello Rainer,

Thank you for your reply.

How can I determine whether the module is transmitting/receiving data using TP2.0 or TP1.6?

EDIT: While browsing with VCDS, I noticed this point:

09 - Central Electrical Systems.
0 - BCM
Byte 24.
Bit 4.

You can switch the transport protocol for the CAN data bus between 2.0 and 1.6.


I just found this online, let's see if it helps me move forward .



As you already mentioned, the ME7.5.x engine control unit (ECU) is used in both vehicles with TP1.6 (e.g., Golf 4/Audi A3 8L) and vehicles with TP2.0 (e.g., A4 B6/B7).
My father coincidentally has an A4 B6 with the exact same engine (1.8t 120kW), and I recently installed and coded the GRA unit.

The next step is to find out which type of Engine Control Unit (ECU) Audi installed.

This isn't about making sense, nor is it about profitability. The Touran will have over 300 horsepower and all-wheel drive. Why? Because I feel like it.

It's as I suspected, everything is now working as it should .
I only had to code the ESP for a gasoline engine.


The ME7 can handle both 1.6 and 2.0 .

Lucky you . Thank you for the feedback!