C63 rear defrost/seats not working?
Thread Starter
Junior Member
Joined: Sep 2012
Posts: 52
Likes: 0
From: San Diego
C63 AMG
C63 rear defrost/seats not working?
so I've noticed that my front seats are not working. They move up down forward and back but the side buttons to adjust the bucket seats Don't work.and now that its winter time I've noticed the rear defroster also does not work. I check ever fuse in the car 3 times each, the engine compartment the driver compartment and the truck. Ice also checked the wiring harnesses under both front seats and they are all plugged in. My fog lights also don't work but that has been going on for along time and they are aftermarket so I'm thinking its an unrelated issue.
Any ideas or is it stealership time?
Eric
Any ideas or is it stealership time?
Eric
MBWorld Fanatic!
Joined: Oct 2012
Posts: 3,704
Likes: 19
From: Denham Springs,LA
'12 C63 Black Series, '12 ML350 BlueTech
If all your fuses and harness connections are fine I would suspect a front and rear SAM failure.
For your side buttons did you check your door module connections behind the front panels?
Could be time to go to the dealership if you don't have the proper tools to diagnose.
For your side buttons did you check your door module connections behind the front panels?
Could be time to go to the dealership if you don't have the proper tools to diagnose.
MBWorld Fanatic!
Joined: Oct 2007
Posts: 2,296
Likes: 380
From: Texas
10 C six trizzle
rear sam feeds power to it. should be fuse 49 and relay kC. Does the rear defrost button stay lit up on the a/c panel? do you have window tint or ever have the window replaced? If it wont stay lit there is definately a problem. If it stays lit it probably has a break in the heating element on the window. Check for voltage at fuse 49, if thats good check for voltage at the relay. test the relay with an ohm meter and 9v battery. does the relay click when activated by the switch. If you have a volt/ohm dmm i can walk you through it.
Thread Starter
Junior Member
Joined: Sep 2012
Posts: 52
Likes: 0
From: San Diego
C63 AMG
The window is tinted but the rear defroster worked since then. The defroster light stays on the control panel it just heat the rear window. Also if I put up the rear shade it will get about half way - 3/4 the way up then freeze and I can't put it up or down. Once that happens the defroster light won't come on either. If I turn the car off and on then it works again. I do have an olm meter.
MBWorld Fanatic!
Joined: Oct 2007
Posts: 2,296
Likes: 380
From: Texas
10 C six trizzle
the rear sunshade is probably a motor problem. Comes as a whole assembly with the sunshade. As for the defrost its pretty strange the light would stay on but it doesnt work. check and see if its sending voltage to the defrost connections at the window. ever get the seats figured out? the side buttons on the seats are the pneumatic portion - which is driven by a separate pump. if it dies non of those functions will work.
Either way sounds like you maybe a little in over your head on this one.
Either way sounds like you maybe a little in over your head on this one.
