SAM panned

I purchased my third Mercedes C Class in February, a 220 CDI Sport (I have never had any problems with any of the others). After 4 days practically every warning light on the dashboard lit up and it was eventually diagnosed as an intermittently failing SAM (signal acquisition module). I was without the car for 9 days. Since then it has covered some 3,500 miles without problem. However, today it has been towed away again to the dealers with multiple electrical problems. Strange warning messages about power steering failure, restraint system failure etc. Air conditioning fan cutting in and out. Radio cutting in and out. At this stage I obviously do not know what the dealer will find this time, although I have to confess that they seem to be pulling out all the stops, but the sad fact is that I have lost confidence in the car. What options do I have and what action do you suggest I could take now?

Asked on 14 August 2010 by DR, Cobham, Kent

Answered by Honest John
This is a problem of can bus electrics where numerous components share the same power source and what gets what is allocated electronically. A fault in any of the components on the same power source can send the whole system haywire.
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