Fuel door is locked when car locked, push on the forward part of door, the aft side will pop out.
loose or broken wires between door jamb and switch
the fuel filter is located under the rear passenger door. in front of the rear wheel.
Open the drivers door and there is a fuse box on the side of the dash you can only see with the drivers door open. The seat fuses are 25 and 41.
Make sure the car is in park, turn off ignition and remove the keys. Don't lock the door. Go to the fuel filler door and gently push on the right side (as you are looking at it). The MB CLS has an over-ride to the locking mech inside the trunk. On the passenger side of the car on the outer wall of the car there is a felt cutout that has a red plastic ring that you can use to open the gas cap (it may take 2 people: one to pull the ring, the other to open the fuel filler door).
usually if you open the door, look in the door edge under the rubber seal right behind the handle you will see a screw, try to tighten it..
Mounted on top and inside the fuel tank.
With the key inserted into the lock.
The fuel pump is in the fuel tank and the fuel tank will have to be removed to access it. If you do not have the skill or equipment to do this properly, I suggest taking it to a shop.
hood release is pulled from the inside of the vehicle near the front of the door opening by your feet. then look for a pull tab under the MB star on the front grill.
Unfortunately I know the answer to this, contact dealership and order another key.
There are 3 ways to open the trunk of the Mercedes cls 500: 1) Use the remote key, press and hold the right bottom button 2) Use button located in driver side door, near front of map pocket. 3) Under trunk lid (approximately center of license plate) there is a lever. pull it towards you with your fingers. NOTE: All doors must be unlocked.
in the boot remove the RHS interior panel , its the green relay