Heaterman1969

I just bought a '99 E300TD and runs great; all electricals checked when I bought it but now none of the front passenger seat controls work. I checked all the fuses in 3 locations.

Any ideas out there?

Musikmann

Congratulations on your car neighbor!

It sounds like you probably found all of the fuse boxes and ruled those out. What about the switches on the door and/or the motor(s)? I think it unusual for all to fail at the same time, but maybe there is sone sort of junction that could be bad? There have been reports of front seats not moving forward and back; at least one was discovered to have had a coin lodged in the track. Good Luck.

Heaterman1969

Thanks for the ideas. I did dis-connect and re-connect all plugs and actually when you operate the switches you can't hear the motors kick in so I've drawn the conclusion that its something electrical between the switches and the motors. I assume there's a 'brain' somewhere that controls wattage, etc to the motors. I haven't had it long enough to start losing pennies, etc. but when my kids were small that was definitely a problem!

I have to take it in this week to activate a warranty so I guess I'll get the ASE man to figure it out.

kmulholl

i had one headrest that didn't move (i think pass side), i changed the battery for maintenence reasons and voila!, the hadrest worked, maybe disconnect the battery for w hile (make sure you have radio security code) - good luck ( mine was 1997 e420)

Heaterman1969

That's easy enough; I'll try it tonight. A friend warned me about these "computers on 4 wheels" so I guess I'll learn the hard way.

lexrex

Does the seat move when you press any of the memory buttons? (Set the current position to #1 so in case the seat moves when you test the other two, you can bring it back where it was.) This will help isolate the problem.

With use, the contact pins in the seat adjustment switch eventually break continuity with the circuit board. If the memory buttons work, you might be able to fix the problem by taking the switch out and putting a few dabs of solder around the contact pins.

Heaterman1969

Thanks for the ideas; here's the current situation. Dis-connected the battery and re-connected - no change. Tried all the memory buttons - nothing.

As a reminder, all the functions were working when I bought it about 3 weeks ago. Now, passenger seat does nothing (but sit there annoying me!).

Does anybody know about the wiring between the door and the seat motors? Are there any more connectors/harness that could have come loose?

mxfrank

I had this problem while the car was under warranty. Somewhere in the car there's a computer that manages the seat position memory functions. When it goes off, for some reason the passenger seat is immoveable. I wish I could tell you where this box is located. It was replaced under warranty, and I never thought about it again.

Heaterman1969

For everyone viewing this thread - I have the car at an ASE mechanic now to activate a new warranty and he's looking at the seat problem. I'll post something here when it's fixed.

Heaterman1969

The non-working passenger seat has been fixed. It was nothing more than one loose connection inside the door panel. So if you have this kind of problem be patient - it may be very simple. I could have spent hundreds on a new "control module" which was the original diagnosis.