Draining the battery completely dead

1991 MERCEDES BENZ 300E
290,000 MILES
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AGHAFFARI0
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  • 1 POST
My mercedes 91 300 e has a new battery and the alternator is charging, yet something in the system is draining the battery completely dead. What could be doing this.

The alternator is good, yet something is draining the battery completely to the point that it has to be put on a charger, a jump start wont work.
Mar 27, 2012 at 4:43 AM
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FIXITMR
  • CAR REPAIR CONTRIBUTOR
  • 9,990 POSTS
you can use test light between battery post and battery (disconnect) and pull fuses 1 at a time to locate circuit that has draw. light is bright until the right fuse is pulled and it goes out or gets real dim.

Check this link

https://www.2carpros.com/articles/car-battery-dead-overnight
Mar 27, 2012 at 5:07 AM
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