I have been having problems with the airbag warning light since last September on my 50,000 mile 2006 Mercedes-Benz CLK 350. The light has been on for the majority of the time and four repairs have so far been attempted. One question that I cannot get a straight answer to is whether, if the light is on, I have functioning airbags. The local non-franchised garage says no, but the dealership is not forthcoming with an answer.

I do have an extended warranty so the cost is not an issue, but the inconvenience of the dealer having the car for a day to diagnose the problem, and a follow-up to fit the new part once it has arrived, has become too much. The last repair was yesterday and the warning light appeared this morning. They now want the car for a week but after four attempts I cannot see that this is going to be of any benefit. How should I proceed?