TemjinX2's $20 seat control battery drain fix
Senior Member
Joined: Aug 2010
Posts: 347
Likes: 0
From: Ontario, Canada
2002 C32 AMG
I'm having this battery drain problem and I can't figure out what it is. I've pulled out 3 plugs from the front portion under the seat. Here's a pic of the plugs.
Will doing this isolate the problem? The seat module is built into the seat correct? I've also noticed that all my dome lights are blown. I've pulled all the bulbs and unplugged the rear dome light as well. It doesn't seem to be working, the battery is still going dead. The car will run for hours on end once the battery is boosted. The battery is also 2 months old, so it's not that. Any other ideas for battery drain? I don't have the time to fix this problem right now, if I want to unplug the power to the seat, which plug is it?
BTW, I also have a DashDAQ logging device which is swithced off manually when the car isn't running. When the car is off, is there current going through the OBD2 port? It's so difficult to isolate the problem as I have to try things one at a time over a long period of time. It's getting annoying.
thanks,
Bryan
Will doing this isolate the problem? The seat module is built into the seat correct? I've also noticed that all my dome lights are blown. I've pulled all the bulbs and unplugged the rear dome light as well. It doesn't seem to be working, the battery is still going dead. The car will run for hours on end once the battery is boosted. The battery is also 2 months old, so it's not that. Any other ideas for battery drain? I don't have the time to fix this problem right now, if I want to unplug the power to the seat, which plug is it?
BTW, I also have a DashDAQ logging device which is swithced off manually when the car isn't running. When the car is off, is there current going through the OBD2 port? It's so difficult to isolate the problem as I have to try things one at a time over a long period of time. It's getting annoying.
thanks,
Bryan
Last edited by Autotechnica; Apr 27, 2011 at 09:27 PM.
Super Moderator
Joined: Jun 2008
Posts: 19,942
Likes: 192
From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
If you isolate the front seat modules & the overhead console A/C temp monitoring fan module you should no longer drain your battery.
Senior Member
Joined: Aug 2010
Posts: 347
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From: Ontario, Canada
2002 C32 AMG
thanks,
Bry
Super Moderator
Joined: Mar 2007
Posts: 5,295
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From: VA
THE C350
You did unplug both set modules right there is one under each seat.
And the black box under the seat is the module that causes the issue the other wires go to the motors and then to the car for power so by unplugging them they are cut off 100% from draining battery. so if both seats are unplugged then the only thing that usually causes issues as glyn said is the overhead console.
And the black box under the seat is the module that causes the issue the other wires go to the motors and then to the car for power so by unplugging them they are cut off 100% from draining battery. so if both seats are unplugged then the only thing that usually causes issues as glyn said is the overhead console.
Senior Member
Joined: Aug 2010
Posts: 347
Likes: 0
From: Ontario, Canada
2002 C32 AMG
I unplugged both seat modules. It didn't work, my battery is still going dead. I'm currently slow charging the battery 14V @ 2-3Amps. I've removed and completely unplugged the upper console/dome light. Hopefully that solves the problem, otherwise I'll be spending my weekend pulling fuses/relays till I find the problem.
Super Moderator
Joined: Jun 2008
Posts: 19,942
Likes: 192
From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
The cause of flat batteries are modules or the whole CANBUS not going to sleep as they should. This thread covers the seat modules. You will find others covering the A/C air sampling fan in the overhead console. These are the common culprits. Comand can also do this if fitted.
If no luck. Pull the earth off of the battery & insert an amp meter or use a cable clamp shunt unit. Then steadily pull fuses from SAM's & cabin fuse block one by one until you find the circuit that is drawing the current.
If no luck. Pull the earth off of the battery & insert an amp meter or use a cable clamp shunt unit. Then steadily pull fuses from SAM's & cabin fuse block one by one until you find the circuit that is drawing the current.
Last edited by Glyn M Ruck; Apr 28, 2011 at 07:25 PM.
Senior Member
Joined: Aug 2010
Posts: 347
Likes: 0
From: Ontario, Canada
2002 C32 AMG
So i think it's the overhead console that's causing the problem. I had the overhead console unplugged and tested the battery this afternoon and it's still at 12.6V. However, does the entire overhead console have to be unplugged or only certain ones? is it the sunroof, dome lights, etc?
I have searched the other threads, and nothing mentions wiring or specific plugs.
thanks,
Bryan
I have searched the other threads, and nothing mentions wiring or specific plugs.
thanks,
Bryan
Last edited by Autotechnica; Apr 29, 2011 at 01:46 PM.
Junior Member
Joined: Aug 2006
Posts: 24
Likes: 0
From: Seattle, WA
2001 C320
I'm going to work on my seat modules this weekend. Between TemjinX2's fix or SGTzAMG's on mymbonline which does everyone prefer? At the end of SGTzAMG thread someone said their SRS light came on, anyone else have this issue?
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Junior Member
Joined: Aug 2006
Posts: 24
Likes: 0
From: Seattle, WA
2001 C320
Well, I did SGTzAMG's fix and so far so good. Everything works and no SRS light. I'll see on Monday if my battery is dead.
Newbie
Joined: Apr 2017
Posts: 8
Likes: 0
From: Orange County, California
2002 W203 C32 AMG
The cause of flat batteries are modules or the whole CANBUS not going to sleep as they should. This thread covers the seat modules. You will find others covering the A/C air sampling fan in the overhead console. These are the common culprits. Comand can also do this if fitted.
If no luck. Pull the earth off of the battery & insert an amp meter or use a cable clamp shunt unit. Then steadily pull fuses from SAM's & cabin fuse block one by one until you find the circuit that is drawing the current.
If no luck. Pull the earth off of the battery & insert an amp meter or use a cable clamp shunt unit. Then steadily pull fuses from SAM's & cabin fuse block one by one until you find the circuit that is drawing the current.
I'm a new c32 owner and you obviously have a wealth of knowledge. A fan behind my COMMAND currently runs nonstop and I've tried searching diligently for a solution to stopping the fan. I still have a battery drain with my seats disconnected. Other than pulling a fuse I cannot get the fan to stop running. Is there a specific update disk to use for the system which will stop the fan? There has not been a surefire solution to this issue posted anywhere on the forum. (Other than just disconnecting the COMMAND fuse)
I would LOVE your or anyone else's advice. I hope you don't mind me sending you a PM as well.
Thanks in advanced.
Cale
