Jun 4, 2015, 06:18 PM
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Alarm went off and now the car has no power!!
Thread Starter
Newbie
Joined: Nov 2010
Posts: 8
Likes: 0
c350
Alarm went off and now the car has no power!!
I have a 2008 Mercedes C350 and the alarm was acting up. The key wouldn't do anything so I got into the car with the mechanical key. still nothing. I disconnected the battery and the siren was still going so I reconnected it. The siren turned off but the signals were still flashing.. two hours later when I returned the car had no power whatsoever. It wasnt the battery because I got a boost and it didnt help. But something weird is happening. One of the license plate lights is dimly lit. I think the car is in stolen mode or something like that. What the hell do I do? Is it really in stolen mode? How do i take it out? Do i have to tow it to the dealer or can I do it myself? Its not under warranty anymore because I imported the car from the US to Canada.
Thanks in advance guys!
Thanks in advance guys!
MBWorld Fanatic!
Joined: Oct 2010
Posts: 1,128
Likes: 19
From: Acapulco Mexico
2010 C300 Sport
Sounds like a lockout between the alarm and the EIS. Others have had this problem, It is expensive to fix, the electronic modules involved aren't cheap.
Check out this thread:
https://mbworld.org/forums/c-class-w...-hate-pos.html
Check out this thread:
https://mbworld.org/forums/c-class-w...-hate-pos.html
Thread Starter
Newbie
Joined: Nov 2010
Posts: 8
Likes: 0
c350
You were absolutely right.. i didnt think this was the problem since my first attempt at boosting it didn't work... thank u!
MBWorld Fanatic!
Joined: Aug 2004
Posts: 1,367
Likes: 3
From: MA
'24 Porsche Macan
A voltmeter will not always show a bad battery as it can read proper terminal voltage but not be able to deliver the proper current. It typically must be tested under load.
MBWorld Fanatic!
Joined: Oct 2010
Posts: 1,128
Likes: 19
From: Acapulco Mexico
2010 C300 Sport
@acr2001: Is the alarm programmed to sound as a warning of a pending dead battery? Or is there actually a separate source for the alarm in case someone tries to defeat the alarm system by disconnecting the battery? Just curious.
MBWorld Fanatic!
Joined: Nov 2007
Posts: 4,433
Likes: 5
From: SFV CA
2008 Black Out C350 Saks Edition / 87 VW GTI
I'm sure your car is under warranty, have tow to the dealer or take the battery to your closest mechanic shop have them charge it and load test it to a 3rd of its cold cranking amperage depending the ambient temperature you should be getting a result of 9.6volts. The car alarm has its own battery, even if you disconnect the battery the alarm still will go off, just another safety MB burglary feature.
