Ah the tipical armrest issue. Sorry, but not very easy to describe, if you drop in a dealership most of them will just pop it back on for you. There is a sequence you need to do with the levers, not easy unless you have done it, sorry
Top of engine. Front right side. Has a little black oil filter looking top with a little MB symbol on it.
Under the armrest that's between the driver and passenger seat. You can get at it easier if you put your hand under the front of the armrest and pull the button that's there, the armrest can go straight up out of the way.
On the console , in front of the armrest
There is an intake and exhaust cam sensor, both are located at the front of the engine in the head. They have 2 wire/pin connectors. They intake cam sensor is the one on the driver's side. See orange circle in picture/link below.
my 2001 catera has cup holders in the armrest. push the button on the front of the armrest once for one drink and twice and it will slide out for two
On the console , in front of the armrest ( according to the owners manual )
How to replace front brake pads on Mercedes s430
If the car shakes when you press on the brakes, you probably have warpped brake rotors, and the squeak is probably some worn out front brake pads. I would have your rotors checked and either replaced (which Mercedes highly recommends or re-surfaced)
Spray some wd-forty in the front where it opens.
Just pull up on the front of the armrest / lid
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how do i remove the electronic front head restraint on a Mercedes c class