Passenger seat doesn't work anymore

[Steve119]

Hi all,

After having done some engine work to my 500E I noticed that my passenger seat is dead.
Left seat works (and everything else in the interior).

I checked the door switch, and I don't have 5v coming to the connectors...
Checked the wiring in the door and no damage, all perfect.
Fuses under the bonnet all fine, as expected since the left seat works.

Electronics is not my expertise, so anyone with hints on how or where to check further? is there a seperate relay or something for each side?

Many thanks!

Steve

 

[gerryvz]

So...confirming....no power at all to any aspect of the seat? Back and forth, up and down, headrest, seat heater (if so equipped), seat memory?

 

[Steve119]

Indeed, right seat is completely dead.
One thing i didn't check is the heating.

I changed the coolant-tank overflow hose to the inner fender, but I don't think I could have touched any wiring by doing that.

It worked prior to changing the timing chain, but then again that hardly has any work near that wiring.

 

[Steve119]

As far as I can see, the power for both seats leaves from fuses F and E, so if the left seat works, only broken wires could stop 5v reaching my right seat.

Unless i'm forgetting something?

Very strange...

 

[Steve119]

Update since the girlfriend is getting annoyed with not being able to adjust the seat!

Found out that power arrives at the right seat module, but nothing leaves towards the door panel in 5V-trim.

So seems that the seat module is dead. Still struggling a bit to remove it, since i cant move the seat anymore. For the 2 plastic tabs on the side i'll have to remove the right side of the frame i think..

Are these known to go bad? Any components inside on the print that always blows up?

 

[Steve119]

Picture borrowed from the master

Looking at this i'm not sure on how i am going to get it removed. I've got the two 7mm bolts done, but there is no space to slide it inwards to free those 2 plastic pins.

 

[edcarls]

I was in a similar situation in a pick-up parts where I need to move the seat forward and upward to remove the seat mounting bolts. I disconnected the cable from the motor and used a cordless drill to turn (rotate/twist) the cable to move the seat.

 

[david hendy]

At the back of the module, towards the rear of the seat are 5 plug in connectors. Two are for the upper seat functions, three are for the seat base motors.

Unplug the three connectors for the base itself and connect a 12V power source to the connectors that lead to the motors. The base will then move as it is supposed too. Giving room underneath to slide out the module, or if you want, give you room to undo the 4 10mm bolts holding the base to the floor.

The center of the seat base where the motors and module sit is held in place by a large "L" shape clip that when un-clipped allows the inboard side of the module to drop down, and the module can slide out.

 

[Steve119]

Thanks! Got it out.
Cant really see anything on the print, but since the connector at the front that leads towards the doorpanel doesnt get any juice it must be dead.

Ebay europe etc however doesnt seem to be a help :/

 

[Steve119]

Ordered a new one since the local benz-breakers couldn't help. Price wasn't insane at 250€, I expected worse.

Thanks for the help guys!