Whenever a passenger is seated in the rear seat (either side) and the car is braked or experiences a bump in the road, the seat belt locks and starts to tighten thereafter with a ratcheting sound each time the passenger moves even a little bit. This tightening continues until the passenger starts suffocating from the pressure. When this happens, the only option is for the passenger to unbuckle the seat belt and start over. But then the process repeats itself. My family members now either refuse to ride in the back seat or they do not buckle the seatbelt and hold it in their hand instead. Obviously this is a safety issue that could result in serious injury in case of an accident. I have taken the car to 2 different dealers on 4 occasions but each time they have told me that the seat belts are working as designed. I have asked owners of 2 other Mercedes cars of similar make and model and they have assured me that this problem does not happen in their cars. I have escalated this issue to Mercedes directly but they have redirected me to one of the dealers and now I can't even get them or the dealer to respond to my emails.

- Danville, CA, USA