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Flat battery with Mercedes-Benz SL500

I have owned my 2003 Mercedes-Benz SL500 from new and it has done 21,000 miles. The batteries were changed for the first time eight weeks ago, as it was not holding the charge. The new batteries are now also going flat if the car sits unused for more than a week. The garage changed one of the two batteries again, but to no avail.

Asked on 17 June 2013 by charlie7

Answered by Honest John
You need to get a local 'car electrical specialist' (www.yell.com) in to test the circuits. This is a very complex car so could be a lot of things. But something you can check yourself is to switch off the interior light completely so it does not come on when you open a door. Often the 'see you out' delay remains open-circuit even though the light goes out, and that drains the battery.

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