Mercedes-Benz Forum banner

1 - 14 of 14 Posts

·
Registered
Joined
·
26 Posts
Discussion Starter #1
I'm sure the car is headed to the shop, but I thought I'd post here real quick to see if this has happened to anyone else or if someone has an idea.

Car: 2000 S430

Issue: Battery is dead every morning. After I jump start, the battery quickly raises to 550 after about a half hour. I drive the car all day, and it's at 800 by end of day (so the alt is charging the battery).

For giggles, took in to advanced to have them test the charge system and they verified the battery and alternator are good. Battery BTW is only 1 month old.

But, every morning, the car is completely dead and needs jump started. Will start, stop, great all day and even into the night if I have to run out. Overnight ? Dies.

So I'm thinking theres a drain somewhere, something is pulling a charge from the battery overnight. I have no lights on, doors are shut, trunk is shut. I've sat out in my car at night to see if I notice something.. nothing.

So there's my situation. anyone with an idea before Mercedes charges me out the ying yang to diagnose?
 

·
Registered
Joined
·
930 Posts
It's a bunch of electronic gremlins.
Check the encyclopedia for some clues. It's usually an electronic part that fails to go to "sleep" after the car is turned off.
 

·
W221 & Audio Moderator
Joined
·
10,863 Posts
There are some steps that may help you locate the malfunctioning part - see the W220 S-Class Encyclopedia, the major heading of "Electrical" - then look for "Battery - sources of battery drain." http://www.benzworld.org/forums/w220-s-class/1508080-w220-s-class-encyclopedia-start-here.html

Some of the links discuss how to troubleshoot this problem. Gabby is correct - often, but not always, it is a part failure that does not allow the CAN bus to shut down properly, so a lot of equipment remains on and drains your battery. In your model year series, this is sometimes the nav disc, but not always.
 

·
Registered
Joined
·
26 Posts
Discussion Starter #4
There are some steps that may help you locate the malfunctioning part - see the W220 S-Class Encyclopedia, the major heading of "Electrical" - then look for "Battery - sources of battery drain." http://www.benzworld.org/forums/w220-s-class/1508080-w220-s-class-encyclopedia-start-here.html

Some of the links discuss how to troubleshoot this problem. Gabby is correct - often, but not always, it is a part failure that does not allow the CAN bus to shut down properly, so a lot of equipment remains on and drains your battery. In your model year series, this is sometimes the nav disc, but not always.
\

I am doing a test light tomorrow. Pull each fuse one by one to see if the leak is identified there.

If not, I don't have the time (or patience haha) to look further and will let the dealer figure it out. In the meantime I bought a portable battery charger until I figure all of this out.

I don't have NAV in my car anymore.. I pulled it out and installed an after market system months ago.
 

·
Registered
Joined
·
26 Posts
Discussion Starter #5
OK. Dealer spent a week and found nothing. Did a draw test and found nothing.

Any ideas? This is a well respected benz dealer. I'm at my wits end.

Sent from my Galaxy Nexus using AutoGuide.Com Free
 

·
Registered
Joined
·
26 Posts
Discussion Starter #6
They are telling me to buy a new battery. Mines 1 month old and starts up just fine if I disconnect the negative every night. So they are wrong

I'm starting to feel like they are just trying to get my car out of there.

Sent from my Galaxy Nexus using AutoGuide.Com Free
 

·
Premium Member
Joined
·
11,367 Posts
If you are prepared to do a bit of sleuthing yourself....take a look at this thread from the W215 forum.

http://www.benzworld.org/forums/w215-cl-class/1625470-w215-hidden-fuses-revealed.html

The electrics on the W215 & W220 are very similar. Pulling out the pre-fuses one-by-one should reduce the time you spend on this problem.

But first, can you quantify the fault?

Can you use a test meter on the current range (maybe milliamps also) to measure how much current is draining there? Remove the earth cable from the battery, and put your testmeter in series between the battery terminal and the earth cable, and note the reading. This leakage must also be flowing through one of those prefuses above, so with the battery re-connected, do the same there. :thumbsup:
 

·
Registered
Joined
·
206 Posts
They are telling me to buy a new battery. Mines 1 month old and starts up just fine if I disconnect the negative every night. So they are wrong

I'm starting to feel like they are just trying to get my car out of there.

Sent from my Galaxy Nexus using AutoGuide.Com Free
Hi,
did you ever find out the cause for battery drain ? thanks.
 

·
Registered
Joined
·
206 Posts
thanks for the update. How did you or the shop pin point the problem to the driver SAM just curious so others and I can learn from it as well.
 

·
Registered
Joined
·
26 Posts
Discussion Starter #11
Just a diagnostic of the sam. Not sure what all that entails. But that's the issue most of the time. 865 was actually a good price considering they threw in an oil change New blinkers and new wipers.



Sent from AutoGuide.com Free App
 

·
Registered
Joined
·
26 Posts
Discussion Starter #12
It wasn't the original dealer i went to. I went to a different Benz dealer and they knew within 12 hours what it was. The first place was just terrible. They also wanted 1100 for the same job w no throw ins

Sent from AutoGuide.com Free App
 
1 - 14 of 14 Posts
Top