Connect New ECUs to K-Line

Hello everyone,

"I drive an Audi A4 B5 from 1996 and I have the following problem: I've added a diagnostic control unit (for the central locking pump), and I'll probably be adding another one (for the alarm system). I'd like to access these control units via the OBD socket. I've already done the coding using a 2x2 > crocodile clip adapter, which worked fine, but using the OBD socket would be more convenient."
Unfortunately, I haven't been able to quickly find any information on how the diagnostic bus is structured, and conducting experiments on a system with multiple control units that each have a four-digit price tag is too risky. In the wiring diagram, the control units are connected to a "combined processor in the switchboard housing"... can this be understood as a bus hub? Or rather, as a large terminal block ? For example, can I safely connect the K-line from the central locking system to the ABS control unit without any further issues (at worst, using a power tap), or would I need to connect it to the aforementioned hub if it exists?

Best regards,

Hi.

If the control units come from the same vehicle or the same model series, you only need to connect the K-line. You can either connect it directly to another control unit or directly to the OBD connector. I also retrofitted the seat memory function in my Golf, and in that case, 2 CAN lines and 1 K-line were needed for diagnostics.


I hope I was able to help.

Sure, here is the translation of the text from German to English:

"MFG" is an abbreviation for "Mit freundlichen Grüßen," which means "Sincerely" or "Best regards" in English.

Hello.

das ist genau das was ich wissen wollte. Wie gesagt, an den Steuergeräten experimentieren ist immer so eine Sache. Ich werde die neuen Sachen jetzt unter der Rückbank beim ABS-Stg. mit an die K-Leitung anklemmen. VThank you very much.

Best regards,