S320 drivers seat won't adjust - PeachParts Mercedes-Benz Forum

amosfella · #1 10-13-2011, 02:21 AM

I was in town today, and wanted to change the position of the driver's seat while I waited, but none of the switches would move the seat one iota in any direction at all... I checked the passenger seat, and it seems that the seat there works. I tried restarting the car, nothing, shutting the car off, taking the key out, and opening the door and adjusting while the door was open. no luck... I pulled the fuses, and all appear to be in good condition.
I recently changed the battery and the horns on the car, as well as doing a brake job....
What would be the next things to check to try to fix this problem??

mbzman · #2 10-13-2011, 02:39 AM

Check the switch and make sure it is getting power.

amosfella · #3 10-13-2011, 10:37 AM

How do I get access to the switch?? I'm betting it will involve taking the door pannel off... How is that done??
I went out, and I'm not hearing anything but the switch click. Unlike the passenger side, where you can hear something click under the seat before the seat moves...

mbzman · #4 10-13-2011, 02:16 PM

Is there a trim piece around the switch that looks separate from the panel? Maybe you can just remove some of the wood trim around the switch instead of the whole door panel. A search should reveal the procedures.

amosfella · #5 10-13-2011, 04:31 PM

Looks about right. Have to try later...
http://www.peachparts.com/shopforum/tech-help/67259-95-s420-front-door-panel-removal.html

amosfella · #6 10-13-2011, 09:49 PM

I should mention that I put a battery charger on without unhooking the battery...

amosfella · #7 10-14-2011, 06:21 PM

Checked the connector at the door switch, no power, but is there supposed to be power there???? The wires look awefully fine for carrying 30 amps...They look more like electric selinoid control wires that work off of resistance...
Is there any way to get the seat to move manually to get it out and test there??

amosfella · #8 10-15-2011, 03:25 PM

Found the controller under the seat. There are 2 wires with power. 12v... is there a way to make the motors move without the computer in?? If I could maneuver the computer out through the back, as the seat isn't right to the floor, is it possible to hook 12v battery, and use the motor leads to move the seat around so I can get the computer in easier??

amosfella · #9 10-16-2011, 12:58 PM

Was able to move the seat by hooking up 12v leads to the motors first through the power leads on the motor connection to raise the seat, and then through the leads connected to the computer. There are 5 wires hooked to each motor lead. The 3 smaller gauge wires are potentiometer or something like that, and the thicker 2 are the power. As the motors are reversible, a current one way through the power wires will move the motor one way, and reversing the current will move it the other way. If one has to move the seat through the motors, the set where only 2 wires connect to the motor are the ones to use.
The motor the moves the seat from forwards and backwards was in the center of the set of 3 motors. I opted to use the leads to move the seat there... I couldn't get my hand in to get the leads to move the seat upwards, so I used a long set of solid steel 'lances' to adjust from the motor...

amosfella · #10 10-16-2011, 04:41 PM

So, I took the computer out from under the passenger's seat, and hooked it up to the driver's seat. Everything works as it should, except the headrest refuses to go up. That was a problem when I tested all controls on the passenger seat before taking it out. I'm guessing that the current shock from putting the charger on the car damaged that as well... Now all I need to find is a piece of zebrano trim and 2 seat computers... I broke the tabs taking the seat switch out of the driver's side....

amosfella · #11 11-09-2011, 02:24 AM

Got a seat computer under the passenger seat today... Headrest isn't moving, but it sounds like the motor is trying to move... Everything else works...