Battery Dead
MBWorld Fanatic!
Joined: Jan 2005
Posts: 2,848
Likes: 15
From: Orange County
2005 C Wagon (No snickering please!)
There are cars in the 2001 to 2003 range that have a problem with a module under the seats that controls the memory seats. These modules consume a large amount of current when active, and only a tiny bit when "asleep." The problem is a failure of the communications portion of the module not putting it in the sleep mode. Bad news is, they cannot be repaired, and are expensive to replace. There are other possibilities for failed parts to draw excessive current from the battery when parked, so the seat modules are not alone.
To find out if the seat module is the culprit, put the seat where you want to sit, then unplug the module. If the battery stays charged, you can then budget for replacement.
A good electric shop with an ammeter can trace the guilty party, and have you back on the road fairly quickly.
To find out if the seat module is the culprit, put the seat where you want to sit, then unplug the module. If the battery stays charged, you can then budget for replacement.
A good electric shop with an ammeter can trace the guilty party, and have you back on the road fairly quickly.
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MBWorld Fanatic!
Joined: Mar 2004
Posts: 2,073
Likes: 27
From: North NJ
2002 C32 AMG, 2013 GLK 350/4, 2015 E63S AMG Wagon
Try the test that Moviela is recommending. This happened to me not long ago. The car would be fine during the day but would not start in the morning. I disconnected the seat control modules and the problem went away.
MBWorld Fanatic!
Joined: Jan 2006
Posts: 3,212
Likes: 8
From: Pasadena, CA
2002 C230K, 2013 BMW 328, 2015 BMW X5
E
Senior Member
Joined: Jun 2003
Posts: 322
Likes: 5
From: Albany, NY
2015 C350 Coupe
The stupid seat control module for the driver's seat went under warranty causing the battery drain. Now that the car is out of warranty, the control for the passanger seat is causing a battery drain. 
The dealership wants $400+ to replace it. I had then unplug it and leave it broken. Anyone know where I can get one and If it can be a do t yourself job?
The dealership wants $400+ to replace it. I had then unplug it and leave it broken. Anyone know where I can get one and If it can be a do t yourself job?
Member
Joined: Nov 2006
Posts: 156
Likes: 0
M5
The stupid seat control module for the driver's seat went under warranty causing the battery drain. Now that the car is out of warranty, the control for the passanger seat is causing a battery drain. The dealership wants $400+ to replace it. I had then unplug it and leave it broken. Anyone know where I can get one and If it can be a do t yourself job?
The dealership wants $400+ to replace it. I had then unplug it and leave it broken. Anyone know where I can get one and If it can be a do t yourself job?
Senior Member
Joined: Jun 2003
Posts: 322
Likes: 5
From: Albany, NY
2015 C350 Coupe
Cheapest online site would be duvalmotorcars.com. Part # you will need: 211-870-47-26. Should be $200 plus shipping and a plug-and-play installation. Good luck.
Junior Member
Joined: Jun 2006
Posts: 52
Likes: 0
From: ATL.GA.
01 C320, 07 Tacoma, 67 F100, 08 boxter S
My Battery is dead each morning in my 2001 C320, and I have noticed a malfunction reading "headlamp sensor, visit workshop". I have not had much time to really check it out-
I believe the lights are automatically coming on when the car comes on- I never had it set like that, and never had any problems before I was bored and was playing with the menus the other day changing settings-
Is this headlamp sensor being out probably whats causing this battery drain???
Thanks,
Dave
I believe the lights are automatically coming on when the car comes on- I never had it set like that, and never had any problems before I was bored and was playing with the menus the other day changing settings-
Is this headlamp sensor being out probably whats causing this battery drain???
Thanks,
Dave
