These instructions relate to the later model W202 C-Class. Early models (1995- 1997) have different door cards and no door-mounted side airbags so a different procedure is involved.
I recently had to replace one of the front door stays in my wife's 2000 Mercedes-Benz C200T (S202).
I couldn't find much documentation online and there were a few difficult parts, so here's how I did it.
To remove the door card/door trim:
1. Pry out the plastic panel around the inside door handle and remove it
2. Remove the speaker grille which is held on by one screw at the bottom
3. Remove the plastic panel around the door latch which is held on by one screw
4. Pry out the plastic airbag sign and remove the screw behind it
5. Pry out the grab handle cover (this is not easy to do, see the photo of the handle to see how it is held in place) and remove the two screws behind it
6. The door card is still held in place by plastic clips so you need to lever or pull to separate
7. Disconnect the door handle mechanical cable by pushing the metal part that connects to the door handle upwards and out, and then the wire can be slid out through a small slot in the handle.
I broke the grab handle cover. I'm not sure the best way to remove these. Mine is now held on to the door card with glue (hope my wife doesn't read this).The door card: arrows indicate items that need to be removed.The grab handle: note the position of the clips that hold it in place.The door with the card removed.The inside of the door card.
To replace the door stay:
1. Remove the rubber cover over where the door stay screws to the car body
2. Remove the Torx screw that attaches the stay to the car body (it will be easier to manoeuvre the stay out of the door if you can remove it with the door as close to closed as possible so the stay is not extended far)
3. Remove the two screws on the front of the door
4. Remove the one screw on the inside of the door
5. Remove the speaker which is held on by three screws
6. Remove the plastic speaker frame which is clipped in place
7. Open up the plastic barrier to gain access to the speaker hole
8. You can now remove the door stay but it does take some manoeuvring to get it out (the only path I could get it out was by taking it out through the recess at the back (outer side) of the door)
9. Installation is the reverse of removal
The plastic barrier is not the type that can be stuck back on. I bought a roll of thin plastic film that you usually put on school books and stuck this over the old barrier and surrounding area. It seemed to work well (so far).Location of door stay screws.
It occurred to me later that you might be able to replace the door stay without removing the door card by just removing the speaker grille, speaker and plastic speaker frame. You may want to look at this option first although I don't know if you can remove the speaker screws with the door card in place. It would make the job a lot quicker and simpler. [Update: No, you can't! Although you could just remove the speaker and reach up to the door stay, there is a screw attaching the door stay behind the door card.]
I also found these factory instructions for removing the door cards which may help.
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