'02 drivers power seat not working

MMatheny · September 18, 2017

Got about 3" of water in it from Harvey. Thought it was the seat control box, ordered used one off eBay, put it in, same thing. The lumbar DOES work, just no seat movement. Checked the fuse behind the dash good. When I press the memory button no beep or anything. Could the used seat controller be bad also? The seat doesn't even try to move. Passenger seat works fine.

MMatheny · September 18, 2017

Update - seat memory buttons DO beep. Seems I can save and recall, but seat doesn't move. Is there another fuse I an unaware of?? Can't believe all seat motors are bad!

gbhrps · September 19, 2017

MMatheny,

One suspect would be the motors themselves, specifically corroded brushes.

Last fall I resurrected the power top motor of a BMW Z4 that had quit working, because it was drowned due to a poor factory design. I was able to remove the motor end case (the end with the brushes) and remove them. They were corroded and stuck in place in their slides, such that their springs couldn't force them onto the armature of the motor to make an electrical contact. A quick clean up to free them up, and reassembly got the motor and the top working again.

You may have the same issue. Pull the seat (disconnect the battery first and wait 20 minutes to allow the airbag capacitor to discharge or it may fire in your face if sparked) and then get at the wiring harness right at the motors. Peel back the plastic covers over the wires just where they enter the motor and identify their colours. Then at the end of the same harness, identify those same wires and the connector pins they are attached to.

Since the motors just reverse the polarity to move them in either direction, apply 12 volts to the two pins and see if the motors work. Then reverse the wires (polarity) to see if they reverse. You should do this on any motors you find in the seat (forward and back, up and down, recline and back up, front tilt and reverse, and so on) If they all work, then you know there is a problem elsewhere. If none of the motors work, they all may need disassembly to clean their brushes, if you can get them apart and have that expertise.

If they all work, take the seat control switch apart and clean all of its contacts with electrical contact spray cleaner. If that gets you nowhere, you'll need a mechanic, since you have power to the seat. Good Luck!