Had a customer in only last week for bodywork with an ML320. Asked us to take a look at his gear selector which could only be moved with a pen pushed into overide slot. He had recently had a diagnostic carried out at Mercedes who told him it would require in the region of £400 labour + new gear selector assembly. They would ofcourse discount their diagnostic fee from his final bill.
It was actually a faulty brake pedal switch!!
This is not the first time we have heard reports like this about our local Mercedes dealership regarding extortionate fees for work that wasn't needed.