romebe

This just happened this week to my 08 CL65. The right lumbar area of the drivers seat was inflated more than normal out of the blue for no reason and is hard as a rock. Mind you, I never really mess with the massage options and always have the setting on 0. Then, as the days went on, the bubble got bigger and bigger and it is now so big that it has stretched the leather of the seat. It is damn near impossible to sit in and driving on it gives me major back pains. I have never seen anything like it nor have not found anything on google about it. I cant put a finger on it as to what could have caused this. I really hope I don't have to pay $5000 to replace this seat because I do not want to put any more money into it. Anyone with any knowledge with this issue please chime in.

southbayslc

Previous owner of my CL63 reported one of the seat cushion side bolster being over-inflated once. The MB tech apparently just deflated it and that was it. Somewhat similar but your situation looks worse...