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Battery kept drained out.. help!!!

Old Jul 23, 2007 | 01:46 AM
  #1  
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2001 C320
Angry Battery kept drained out.. help!!!

Need help from all members.

I own a 01 C320 and my car power are totally drained out if parked morre than 8 hours. I mean totally out of power, can't even unlock the car. I thought it was a bad battery, but when I jump the car, it will charged the battery and I can drive and stop all day. But would not last overnight. I made sure all lights are off every night and radio & ac are off. But still the power is TOTALLY DRAINED.!!

Anyone else out there having the same problem??
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Old Jul 23, 2007 | 01:55 AM
  #2  
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give this some consideration (a try).... CLINK
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Old Jul 23, 2007 | 02:20 AM
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And if it's not the seat controller it could be a bad SAM. Anything that will keep the CAN B from going to sleep will cause a battery drain. It's best to let the dealer diagnose it. They have the test equipment to do this:

http://www.babcox.com/editorial/ic/ic030538.htm
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Old Jul 23, 2007 | 04:54 AM
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another thought: if it was really totally drained, no jump start, no driving around
is going to replenish the battery. it must be examined, electrolyte checked for
specific gravity, fluid topped off, and then recharged using a stand alone trickle
charger - again, not the car's charging system.

having said that, i wonder whether it's also possible that you're only placing a
superficial charge back into the battery and it's self discharging. so, pop the
cap and check the fluid.
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Old Jul 23, 2007 | 08:19 AM
  #5  
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It is also possible to have a defective battery,, could have a cell going bad.


BTW where can a replacement battery for the E500 be purchased. Mine is a Bosch with apparently a center tap for low voltage to a wiring harness.

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Old Jul 23, 2007 | 01:59 PM
  #6  
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2001 C320
New Battery

Battery is new.. Only 1 month old
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Old Jul 25, 2007 | 08:25 AM
  #7  
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Originally Posted by prinzron77
Battery is new.. Only 1 month old
SO!.. Is it good? Could still be defective.

1) Did you have this problem before the new battery?

2) If No,, then consider the battery

3) If Yes was the old battery confirmed defective.

4) If Yes consider the replacement battery defective

5) If No check battery out of the car to see if it fails

6) If fails replace it

7) If not look for short

To not consider a new battery as defective might lead you down some really expensive work.

Have fun,, and a nice day.
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Old Jul 25, 2007 | 09:37 AM
  #8  
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werd....doing a few definitive checks on the battery takes less than 15 mins.
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Old Jul 26, 2007 | 12:56 PM
  #9  
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A Midtronics Battery Tester is the tool to quantify the battery condition. It will define the state of charge and the battery capacity. This will permit an accurate judgement of the battery health.

The "dark current" may be measured using a multimeter.

The charger output and components may also be measured and compared to standards.

Battery problems suck, but may be resolved using normal analysis and by following procedures.
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Old Jul 26, 2007 | 01:56 PM
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Originally Posted by vettdvr
SO!.. Is it good? Could still be defective.

1) Did you have this problem before the new battery?

2) If No,, then consider the battery

3) If Yes was the old battery confirmed defective.

4) If Yes consider the replacement battery defective

5) If No check battery out of the car to see if it fails

6) If fails replace it

7) If not look for short

To not consider a new battery as defective might lead you down some really expensive work.

Have fun,, and a nice day.
This is a good general guideline, but it ignores the fact that all MBs, and this model in particular, suffer from a particular problem: a bad controller (often the door control module) preventing the CAN-B from going to sleep when you remove the key. This causes a 1+ amp drain that discharges the battery in less than a day. If 7) were "If not look for an unusual current drain," you'd have it covered. In any case, a new battery draining down you can jump right to "diagnose non-sleeping CAN cause." It's happened to me with two MBs. One was a bad mirror control module and one was a bad rear SAM. The symptom was the same: CAN-B not sleeping and battery draining overnight.
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Old Jul 27, 2007 | 09:50 AM
  #11  
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Originally Posted by whoover
This is a good general guideline, but it ignores the fact that all MBs, and this model in particular, suffer from a particular problem: a bad controller (often the door control module) preventing the CAN-B from going to sleep when you remove the key. .

NOPE didn't discount the MB issue. Statistical probability would indicate that batteries fail more frequent, eventhough there are other issues.

I always go simple cheap first, before going into hard wire stuff.


Besides the defect was covered in previous post. So Nope didn't discount,, just didn't cover previous ground. Are we having fun...
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Old Jul 27, 2007 | 10:02 AM
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Okay, this is what to do:

With car off detach negative post from Battery. Attach a digital multimeter to the detached terminal, and the other to the actual battery post and measure amps. You will then see you probably have an amp draw witht he car off. Wait about 10-15 mins and see if it is still there.

If it is still there unplug the seat control module under the drivers seat.

IF the amp draw doesnt change do the same to the passenger seat control module.

One of these is probably bad causing CAN to stay awake. You should have less than a 100ma draw with the car at rest. Replace the seat module that makes the amp draw drop when unplugged. I have seen both go bad in the past but its usually one or the other.
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Old Aug 10, 2007 | 10:16 PM
  #13  
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'02 c230k coupe
I have the sale issue with my ’02 C230. Had 3 new batteries in two years, the dealer once told me it was my battery not being a MB brand battery. I’m going to test the seat control unit, if it fails I’m taking it to an independent MB repair center.
F--- the Stealership, they think because one owns a MB one knows nothing about cars.
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Old Sep 25, 2007 | 07:00 PM
  #14  
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2002 C230 Coupe
Hi Guys,

I have a 2002 c230 Coupe and I traced my battery drain back to the seat controller (I unplugged the controller and the car has been rock solid for a month now). My question is, how can I go about fixing the controller? Do I need to replace it out right? If so, where can I pick one up at a reasonable price? Does anyone have the part number for the seat controller on a 2002 c230 coupe?

Thanks in Advance (and great thread btw!),

Rich...
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Old Sep 25, 2007 | 08:20 PM
  #15  
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C32 AMG
Originally Posted by prinzron77
Need help from all members.

I own a 01 C320 and my car power are totally drained out if parked morre than 8 hours. I mean totally out of power, can't even unlock the car. I thought it was a bad battery, but when I jump the car, it will charged the battery and I can drive and stop all day. But would not last overnight. I made sure all lights are off every night and radio & ac are off. But still the power is TOTALLY DRAINED.!!

Anyone else out there having the same problem??
Hi i had the same issue with my C32 amg and whent through a lot of heartache and money and embaressment, here are my suggestions no.1

1) battery check (constant jump starting killed it and left me with other issues, which i think is from constantly jumping)
2) underseat module ( i beleive the above knackered the underseat module)
3) command unit drain (finally fixed by dealer by replacing head unit) under warranty (internal bill was £3000 ( i should sub contract what a cool way of making money, as you can buy a new unit for £500 or buy a hotfix disc from the dealer for about £10 unfortunatley i never got the part no.


Has anybody else got this disc with instructions please pm

Good luck
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Old Oct 6, 2007 | 03:17 PM
  #16  
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truck
its usually either the l or r ft seat control mods or the l or r DCM's(door control modules),
it should be less then 50 Ma draw with a meter. disconnect each control module to see if it drops..just make sure doors are closed,trunk closed,key out..

Last edited by RogueMBtech; Oct 6, 2007 at 03:19 PM. Reason: ad
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Old Oct 7, 2007 | 11:42 PM
  #17  
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Slk32 AMG 2000 Model
It Might be within 2reasons of this sort of problem
the first is

your battery time-line is over
Anote"You Said Your Battery Is New Go Check The Battery Again Maybe There Is Something Wrong With It"
the second is
Maybe The Car Dynamo Isnt Working Right

cause i had a similure problem on
my E55

Last edited by Djinn; Oct 7, 2007 at 11:48 PM.
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Old Oct 9, 2007 | 04:00 PM
  #18  
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2004 E500 Wagon 4Matic
Don't know if this will help, but here's my experience.

I bought the car about 6 weeks ago. A week after I drove it home I went to start it on Saturday morning and there was very little power left in the battery. Tried to start, but no attempt to fire up. Plus big red warnings about low battery, SBC unit, etc. I slow charged the battery through Saturday and overnight and on Sunday it was fine.

Now the first week I had it, I discovered this forum and each day I would try and program a convenience feature. One I tried mid-week was the side mirror downturn when Reverse is engaged. I didn't think that worked. But on the Thursday I noticed that the easy in/out feature suddenly came alive. Pull the key out and the steering wheel goes up and in, and the seat moves back. I thought "OK, didn't mean this one, but I like it".

My personal theory is one of these "features" just didn't stop it's motion. Like the seat continually tries to move back, or the steering wheel keep trying to raise. This is just a theory. But in disconnecting the battery I understand all convenience features went back to factory default, which I think is all off.

Since the recharge I have not had a repeat (touch wood). And the convenience features, well, I don't really need them so I don't miss them at all.

jim
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Old Oct 22, 2007 | 09:14 AM
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2001 c320
Battery drain

I just went through the same thing - finally had the dr and pass seat sensors replaced and that solved the dead battery - I have the feeling that this occurs predictably and shoud be part of a recall - any others experience this ?
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Old Oct 22, 2007 | 11:18 AM
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Originally Posted by champdog
I just went through the same thing - finally had the dr and pass seat sensors replaced and that solved the dead battery - I have the feeling that this occurs predictably and shoud be part of a recall - any others experience this ?
Recalls are for safety-related defects. It's hard to make the case that your battery going dead overnight in your garage will cause an accident.

That said, the design is not a good one. These controllers fail at a high rate, in a way that keeps the CAN-B from timing out and therefore draining the battery. It takes (took?) a major design change to prevent this failure mode. I don't know if the controllers were redesigned to make them more reliable. I had two bad controllers on an S55, fixed on warranty.
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Old Nov 9, 2007 | 08:37 AM
  #21  
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00' CLK 430
Battery Drain

Hi all,
I have the same car (2002 C230 Coupe) and also have the same problem (driver seat controller). I am also looking the the part if anyone can help..

Thanks

Originally Posted by RichW
Hi Guys,

I have a 2002 c230 Coupe and I traced my battery drain back to the seat controller (I unplugged the controller and the car has been rock solid for a month now). My question is, how can I go about fixing the controller? Do I need to replace it out right? If so, where can I pick one up at a reasonable price? Does anyone have the part number for the seat controller on a 2002 c230 coupe?

Thanks in Advance (and great thread btw!),

Rich...
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Old Nov 9, 2007 | 11:53 PM
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Whatever there's gas in...
My S-Class was doing the same thing, my son took out my Navigation disc and it hasn't done it since!

If you have COMAND, It wouldnt hurt to give it a tryy.
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Old Nov 10, 2007 | 12:17 AM
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SL55
could be you left lights on
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Old Nov 10, 2007 | 08:24 PM
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C320
Hi there,

I also have a similar problem that I'm now trying to investigate. Maybe if we combine our efforts we can find out the root cause. Check the link below.

https://mbworld.org/forums/showthrea...ht=door+module
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Old Nov 11, 2007 | 05:59 PM
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same condition re:2002 C320 wagon

I'm also have the same condition,at one time the left/front seat would not move back?Can some one email me the diagnostic from the manual?
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