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Battery Drain Caused by Fault SOS Issue?

4.9K views 4 replies 5 participants last post by  nationwideauto  
#1 ·
Hey guys, I have a 2005 S430. I've been dealing with a battery draw for a little while now. I pulled the battery and tried to charge it for 24 hrs, and never got over 12 volts, so I replaced the battery (this was about 1-2 weeks ago). Today I went to start my car and it's completely dead again. No lights on the dash or anything.

That being said, I have two messages coming up on my screen before the drain. One is an Airmatic warning (which the previous owner told me that sometimes you just need to bump the cable a little to fix that), but another and more persistent issue is an error I'm getting that says something along the lines of SOS Malfunction - Drive to workshop and is attached to a light in front of my rearview mirror.

My question is, can this SOS issue be draining my battery and if so, how would I fix that? Thanks!
 
#3 ·
Yeah, this calls for a session with STAR Diagnostic System (SDS).

Dad's car has recently developed a similar battery-draining problem that I've got to figure out after the project 2006 S500 4Matic is ready to drive. Dad's car has already gone through two batteries, so for now (sorry, Dave!), I've disconnected the battery.
 
owns 2003 Mercedes-Benz S600
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#4 ·
so for now (sorry, Dave!), I've disconnected the battery.
:ROFLMAO:

It's OK once in a while, especially for those of us who know about Normalising stuff and also have SDS for some of the items like PTL which cannae be done without that ;)

Personally I'd have plugged it into a Battery Maintainer, but of course that does depend on where your 'Dad's car' is parked whether that's feasible or not for you to do ;)