CAN-Bus not communicating with anything

[Marc_986]

Not an expert on this, but maybe someone with more knowledge will correct me or it is already helping you out a bit.

As far as I am aware there are two CAN busses on these models. One for the powertrain and one for the comfort / hvac stuff.

On the cluster:
Yellow: CAN comf high
Black: CAN comf low
Blue/White: CAN antrieb high
Gray/White: CAN antrieb low

ABS is on CAN antrieb
DME / ECU is on CAN antrieb
Tiptronic is on CAN antrieb

Radio is on CAN comf
Clima is on CAN comf

It looks like the CAN antrieb wire colors are also used for other functions in the engine wiring loom.

[mrian]

Thanks Marc_986, that's very helpful. From what you're saying, I have a problem with both CAN-systems, which in my opinion would rule out the CAN-data wiring having a break somewhere being an issue.

That leaves me with the instrument cluster being faulty (seeming more likely now), or an issue with the CAN-power supply wiring, if such a thing exists.

I don't believe I clarified, I have no noticable issues with my instrument cluster. Whatever the problem is, I believe it is isolated to the CAN-computer.

By any chance, does someone know the pinout of the connectors on the instrument cluster, and which spots the CAN-related pins are? I think my next step should be to check for voltage at the power supply pins. If that check passes, replace the instrument cluster, and if not, repair the wiring.