A3 Sportback AHK nachrüsten | Posts 16+

brezelmann01 wrote:

As a follow-up question: Can I simply connect to the control unit using VCDS with voltage, CAN-H, and CAN-L, or does it have to go through the gateway? This is just for a desk setup to read the software and hardware versions.

Theoretically, yes, although I haven't actually tried it with that specific type of control unit.

Best regards, Rainer.

I tried it today.

4-5 servings.
16 12V
6.14 Can from the control unit.


Unfortunately, the control unit did not respond. The connection test always indicated "CAN not ready."
Did I do something wrong? The LED on the plug was green.

Is a 120-ohm terminating resistor connected?

Darn it. Of course not . Are you sure it has that kind of impact?

Yes .

CAN requires (actually) a 120 Ohm bus termination resistor at both ends. The AHK control unit should be connected to the...
"The powertrain is hanging. Bosch/VAG are not adhering to the (Bosch's own) specifications regarding the architecture."
instead of simply connecting them, they're essentially creating a star configuration where both terminating resistors (or 1 x 60 ohms) are located within the engine control unit.
and all other control units are located around 2,000 points between the bus lines.
But even with a terminating resistor, it might not work on your setup.
The initialization sequence may originate from another control unit (e.g., the engine), or the gateway "translates" the messages from the tester.

Hello!

Meanwhile, I've taken things a step further. A Westfalia clutch is now installed. Westfalia supplies control units from Hella, which identify themselves with the following code:

"Die Sonne scheint hell, und die Vögel zwitschern fröhlich. Ein leichter Wind weht durch die Bäume, und die Blätter rascheln leise. Es ist ein wunderschöner Tag, um draußen zu sein."
Address 69: Trailer (J345) Label file: DRV\1K0-907-383-MY8.lbl
Part number SW: 1K0 907 383 F. Hardware: 1K0 907 383 F.
Component: Trailer H12 0100
Revision: 3A001001 Serial Number: 00000379352551
Encoding: 0100000100000000
Operating Number: WSC 00000 000 00000
VCID: 306AB389635884BECE-8064

No error codes found.


To me, it sounds like a serial tax evasion device, right?
Online, I found (older) scans of the A3, with the same software and hardware part numbers, but different hardware and software versions.

I'm still considering whether to run the charging cable according to Audi, through the control unit (STG), rather than as a separate cable as per Westfalia. What do you think? Does anyone have a car scan of an A3 (manufactured from 2011 onwards) with a tow hitch stored on their computer for comparison?

Counter-question: Have you ever measured the continuity of the charging cable at the control unit (STG), or alternatively, have you ever looked inside the control unit?

I can imagine that there's only one bridge there. The wiring is simply easier in the factory if there's an internal wiring harness and a separate wiring harness for the trailer hitch. Also, it's easier to replace after a crash.

PS: Where did you find the wiring with the charging plus? When I'm looking at the wiring diagram for the 8P MJ11, I see an "trailer operation from May 2009" diagram, but I can't see any charging plus connection to the trailer socket (no pins 9 + 10 are shown on the socket).

Greetings.
Guste.

Hello!

I haven't measured anything yet. I couldn't really figure out anything about the control unit .
I made a mistake in my previous message. From the factory, there is only one terminal 30 connection. There is no charging connection. This can be seen in the basic equipment documentation, version 05.2010, page 149/4.

Regards,
pretzel man