Black_Mercedes

2011 c63 p31

So for some reason the Bolstering in my car keeps blowing fuse 56 in the trunk of the car.

Im not sure if its driver seat or passenger seat that's doing it. Some days it will be good for a couple of days some times it blows as soon as i put the fuse in.

Does anyone have a wiring diagram or some information on whats causing it?

I looked it up and some people said the wiring in the driver seat becomes frail?

I also noticed somedays it says my right licenses plate light is out i have to go outside the car and tap on it pretty ghetto for it to turn on. Not sure if that has anything to do with that line on fuse 56.

Plutoe

Post your VIN!

Adi-Benz

Lol @ ghetto

Did you check the connections?

Black_Mercedes

I will post vin number as soon as i get home from work. Thanks

Yeah i pulled off the back cover cleaned everything up it worked.

Then i closed the trunk and the error popped back up. Had to go back out and flick it LOL

Black_Mercedes

Vin WDDGF7HB9BF569057

DAMG63

Had the same issue with mine. Took into dealer (under factory warranty still). They started off by replacing fuse as well. Went out within 5 minutes. Traced a short back to drivers bolster motor. Replaced both bolster motors in driver/passenger seat. Issue gone. Hope this helps!

Black_Mercedes

All the motors work it seems to happen when i move the passenger seat forward or backwards.

DAMG63

I would bet theres a short or a wire might be getting pinched.

Black_Mercedes

anybody have a wiring diagram for the seats? Wondering if i should take them out and have a look or just forget about it

JimmyR

Happened on my pre FL. There is a wiring harness that depending on position the power seat is set to gets kinked/pinched near the "hinge" of the seat. Eventually wears thru the wiring insulation, creating a short and blowing the fuse. I had this fixed under warranty, was told it was a "seat out, half day" job.

JimGnitecki

I can see why this would happen, especially if you often carry a rear seat passenger, as the passenger side front seat move forward and backward TWICE for each ride (when the rear seat passenger enters and when he/she exits). Given enough time, the wiring insulation WILL wear through.

This could be either a design or assembly error.

Make me think about proactively finding the offending wireset and wrapping it in a wiring protector split-tube before MINE fails, as our adult son lives with us and is a frequent rear seat passenger.

Anybody got a picture of the wiring location?

Jim G

ZephyrAMG

Thank you as I have been trying to figure this out...

Both my front seats don't work for lumbar support...

Black_Mercedes

Any body have a diagram showing which of the wiring goes bad on the seats? Im thinking about taking it out over this next weekend when i have time. I had to buy a box of fuses at harbor freight lol

KGc63

Both seats run off the same fuse. I had this issue when I first got mine a few months ago. After temporarily adding individual fuses for each seat to diagnose, the shop cut out and spliced in a section of the harness that powers the bolsters.

ZephyrAMG

I would also appreciate some pics or a diagram. Very odd for the lumbar support to keep blowing...

Black_Mercedes

I didn't figure to test it before i picked up my car lol. Now its gonna bug the **** out of me.

masonpardo

Might be totally useless but I had fuses that kept blowing because I had coins in my cigarette lighter.