Hi there, newbie Benz owner, and seeking help with a curious problem.

i have an 08 W204 C220 CDI, brilliant car, but has an electrical issue.

i have no steering wheel buttons, or horn working. I had assumed it was the clockspring, so ordered a new clockspring, and taking my time, I have replaced said clockspring, and it has made no difference. Also replaced the PCB in the steering wheel that is mounted on the airbag frame. Also no difference, still no operating buttons.

there is power into the steering wheel, but buttons do nothing when pressed.

I have checked the search function, and read a lot of threads on steering wheel controls, but have been unable to find any threads with an issue similar to mine.

I’m taking a stab here, and guessing that the controls are sent via Can-bus to the radio, and that there may be a can-bus communication issue.
have these got a module that controls steering wheel buttons?

any help would be greatly appreciated

 

Just to add to this, I’ve purchased an icarsoft car pro. I’m getting a fault code of U100800, Lin Bus 1 has a malfunction.
also have a code for auto headlights and auto wipers sensor malfunction. B221D49 and B225F49
also standing light 1 and 2 fault codes B16EF15 and B179B11
Also output for right license plate lamp B16EB15

these appear to be from the Steering Column Module and the Drivers Side SAM - front


if anyone has any ideas, it would be greatly appreciated.

I’ll check all connections again tomorrow, see if I’ve missed something, but would appreciate any ideas if anyone has had this issue before.