w203 Battery Dead
12-11-2006, 09:59 AM
#2
MBWorld Fanatic!
A battery drain is usually caused by a CANBUS (one of the fiber optic networks that are a modern car's nervous system) not "going to sleep" when the car is turned off. The -B (body) bus can drain an amp, enough to drain a battery in a couple of days.
Any controller (like a power seat switch module) that goes bad in a way to put static on the bus can do it. Often, one of the two SAMs (signal acquisition/activation module -- the system's brain) goes bad with the same consequence. A good tech has the tools to diagnose it.
This is a very good, but technical, description of how this sort of problem is fixed:
http://www.babcox.com/editorial/ic/ic030538.htm
Bottom line: take it to the dealer or a shop with a very good electrical system specialist.
Any controller (like a power seat switch module) that goes bad in a way to put static on the bus can do it. Often, one of the two SAMs (signal acquisition/activation module -- the system's brain) goes bad with the same consequence. A good tech has the tools to diagnose it.
This is a very good, but technical, description of how this sort of problem is fixed:
http://www.babcox.com/editorial/ic/ic030538.htm
Bottom line: take it to the dealer or a shop with a very good electrical system specialist.
12-11-2006, 12:15 PM
#3
MBWorld Fanatic!
Originally Posted by whoover;
This is a very good, but technical, description of how this sort of problem is fixed: [url
This is a very good, but technical, description of how this sort of problem is fixed: [url
http://www.babcox.com/editorial/ic/ic030538.htm[/url].
12-12-2006, 12:18 PM
#4
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2001 C320 Battery drain.
It happened 6 months ago, it was the driver seat module.
Just yesterday, again, this time it is the passenger side module.
I don't know how much is the fix cost, since the car is covered under
extended warranty.
For simple diagnostic, just unplug the wire connection to the
module to see if the drain continuous.
It happened 6 months ago, it was the driver seat module.
Just yesterday, again, this time it is the passenger side module.
I don't know how much is the fix cost, since the car is covered under
extended warranty.
For simple diagnostic, just unplug the wire connection to the
module to see if the drain continuous.
12-21-2006, 08:06 PM
#5
the can bus isnt fiber optic, the D2B and MOST circuits are though.
12-21-2006, 08:54 PM
#6
MBWorld Fanatic!
12-21-2006, 10:21 PM
#7
lol, no doubt man.
One of the seat control units is like 200, and the other is like 350 or 400 I think.
I just did some the other day and I reminder one being a bit more than the other. Usually they are the cause of 203 draws, if the drain is still present unplug the overhead panel/unit
One of the seat control units is like 200, and the other is like 350 or 400 I think.
I just did some the other day and I reminder one being a bit more than the other. Usually they are the cause of 203 draws, if the drain is still present unplug the overhead panel/unit
