What is life like with your car? Let us know and win £500 in John Lewis vouchers | No thanks

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.
Similar questions
I have been a FIAT owner for a number of years now, but it has come to my attention that my 2006 Panda with 70,000 miles on the clock now needs work for a power assisted steering failure which my dealer...
I have a 2008 Mitsubishi Outlander D-ID 2.0. I'm having some real problems with my steerin - at the moment the steering feels really sloppy and the steering wheel pulsates (kick back) in the opposite direction...
My daughter has a 3 yr old Mazda2. For some time it has suffered a knocking in the steering at or near full lock. Mazda dealer has regreased steering column on several occasions with only temporary improvement....
Related models
A big improvement on the previous C-Class. Feels well built and robust. Very comfortable and refined. High quality ride. Good CDI diesels.