battery dies over night on 2001 Mercedes-Benz C240

what causes the battery to die over nite, and when it sits for a few hours? i cant hear anything running when i turn the car off. there are no lights on in the car. any help would help save cash and unwanted stress on the lady of the house

Asked by for the 2001 Mercedes-Benz C240
the seat control modules are running causing the dead battery. I have a 2001 C240 and had the same issue the module is located under the front seats, you need to unplug both cables under both front seats. this should stop the battery from dieing but you will not be able to move your seat unless you reconnect the cables.
I have a 2002 model doing the same thing.. Mercedes wanted $812.00 for the module. My problem is with the passenger front seat. There are four sets of wires and quick connects. Which is the seat control module?
4 more answers
If you have power seats, try unplugging your seat module overnight and see if that stops it. I had a draw in mine and they want $1400 at the shop to replace them
Where are the plug underneath the seats?
seat control modules and you can buy on line a remanufact and install yourself for about $235 each. try the Parts Geek.
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