My 1998 C230 had a drivers headrest that would not adjust. I quickly tracked the trouble down to the motor itself (in the seat back just under the headrest). I puzzled a lot longer about how to get the motor assembly out so that I could repair or replace it. Since I now have it figured out and repaired I thought I would provide the info for anyone who ever runs across the same problem. I am not sure how common this problem is although I know that some of the problems on this car are quite common, such as the climate control display "fading out"/losing segments/digits (I am working on that one). I assume these instructions would apply to 97 and 98 C230 and C280 at least.

Symptom: Head rest will not go up or down when the button is pushed.

Diagnosis: "Cold" solder joint on the PC board at the motor.

What I found: There is a small PCB about 1" square, soldered onto the top of the electric motor in the seat back. This PCB is only partially exposed, where there is a little connector for the cable that attaches to it, supplying its power. I found that this board was loose and that if I pushed it one way or the other while someone pushed the headreast button, that the headrest would operate (door had to be open of course, or key in the ignition). So I assumed a loose connection of some kind.

What to do:

Remove seat back trim panel (the part that has the magazine pouch on it). There are 2 Torx T-15 screws at the bottom. Remove these and the panel basically falls off. (The screws are close to the floor so you will have to work by feel probably) They angle slightly forward so angle your screwdriver slightly forward for best results.

Once that is off you can try to determine if you have the same problem by wiggling the PC board.

To remove the motor/adjuster assembly:

Remove the headrest: The 2 chrome rods from the headrest attach to the black plastic adjuster at some "snap" fittings. There are 4 slots at each fitting. Work on seperating the left hand chrome rod first. While pulling up on the left hand side of the headrest with your left hand, twist a large blade screwdriver in one of the slots to loosten it and let the chrome rod pop out. Once this side is loose you can get the right side out more easily. Now pull the headrest up and out of the way. Now pull the electrical connector off of the PCB. It is tiny, but try to pull on the connector and not the wire. Once that is off the last thing to do is remove the motor/adjuster assembly. This assembly is attached with a "slide snap" system that uses no fasteners. Put your hand on the top left hand end of the assembly and push to the right HARD. When you have pushed hard enough, it will slide abruptly to the right about 1/4". Then you can pull it straight down and out. At this point I disassembled it and resoldered the bad connection. You might want to just replace it if you don't have experience with soldering.

Hope this helps some one some day!
Mike

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1998 C230 330,000 miles (currently dead of second failed EIS, yours will fail too, turning you into the dealer's personal human cash machine)
1988 F150 144,000 miles (leaks all the colors of the rainbow)
Previous stars: 1981 Brava 210,000 miles, 1978 128 150,000 miles, 1977 B200 Van 175,000 miles, 1972 Vega (great, if rusty, car), 1972 Celica, 1986.5 Supra