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I have a problem with the driver's seat on my 2003 E320. The back part of the cushion does not go up an down.
Here are the symptoms:
No DTCs come up. It's communicating with the motor's hall sensor.
All other motors work.
The back part of the seat is stuck in the up position.
When I press the switch on the door for up. I hear a click.
When I press the switch on the door for down. I hear no click.
One of the relays in the seat control module has failed. The easiest solution is to replace the seat control module located under the seat. You can pull the seat the get access to the module, read the PN printed on it and buy an identical PN on ebay.
Thanks for helping. I really appreciate it. Is there a possibility it could be the switch. If there's no current coming from it then it would be another reason why the relay didn't click.
Thanks for helping. I really appreciate it. Is there a possibility it could be the switch. If there's no current coming from it then it would be another reason why the relay didn't click.
Not likely. The failure is usually in the controller. If you had a STAR diagnostic tool or Foxwell nt520 you could could actuate the seat through the scan tool. If it moves you'll know the failure is at the switch.
One thing you can do when you have the seat unbolted from the floor is to hotwire the appropriate seat more to move it back down into a good drivibg position for you. All the seat motor functions are marked on the housing of the controller.
Not likely. The failure is usually in the controller. If you had a STAR diagnostic tool or Foxwell nt520 you could could actuate the seat through the scan tool. If it moves you'll know the failure is at the switch.
One thing you can do when you have the seat unbolted from the floor is to hotwire the appropriate seat more to move it back down into a good drivibg position for you. All the seat motor functions are marked on the housing of the controller.
I am leaning heavily towards the motor not being the problem. I had a fore-aft seat motor give out on my CLK and on that car the module made clicking sounds for every switch position but the motor didn't move.
I have an iCarsoft MB II. I wonder if that could move the motor? I might try tomorrow to get the leads from the passenger seat and hotwire the motor on the driver's side to check its functioning.
BTW the symbols HH, HV, LV and LK, I assume are seat cushion up down, seat cushion angle, backrest recline and fore-aft respectively. Is that correct?
I have an update. I took the car to a Mercedes specialist who diagnosed it to be a seat switch. He replaced it and it now works properly. Thanks for all your help.
05-18-2020, 10:18 PM
