I have a Merc E207 coupe 2015 40k miles which has just had a B service with my local authorised Mercedes service agent from whom I purchased the car and have serviced it since. I have had a problem with the panoramic sunroof the first time I used it following the service. I has always worked perfectly. The window would open fully as normal but when I tried to close it it would reverse when it reached about 6 inches from the closed position. This happened repeatedly. I managed to close it by applying a pump action closing it about an inch at a time. The next time I opened it exactly the same thing happened so I brought it back to the Dealer. They said they would put it on diagnostics and said that was giving several (unspecified) errors. They would not allow me speak to the engineer so was dealing with a less than helpful reception who was interpreting what they were told and said I would have to book it in for a full diagnostics at a cost of €350. My question is should the B service not include diagnostics, what diagnostics would they have run when I brought it back and what diagnostics will they run that costs €350 before they do anything? Thanks in advance.