One thought has just popped into my head how did you remove the light switch if you accessed it from underneath you could have dislodged one of the connectors on the steering column since the seats and the steering wheel are tied together that could be the cause i suggest you check all the connectors behind there and check they are all securely connected.
Just give them all a push to check they are tight don't remove any re-insert them because there are airbag wires under there that when disconnected will shut down the SRS until MB re-enable it again you would need to explain just what you where doing under there.
Are you any good with a wire crimper? if you are then order the parts from MB and do the job yourself if not don't risk it CAN wont like a dodgy connection one bit.
__________________ One thing you will learn with German cars - If it's simple it ain't happening. |