Ptrigg17

I love my 2012 E550 Cabrio and with 42K this is the first problem I’ve experienced. When I start the car the presenter starts to move out then quickly retracts. If I push the dash button it will present the belt and retract properly. Prior to this problem the seat belt would retract slowly when unbuckled. I am not sure if the symptoms are related . It sounds like something is restricting the mechanism. Can anyone shed some light on correcting the problem.