1991 BMW 525i

1991 BMW 525I
265,464 MILES • 6 CYL • 2WD • AUTOMATIC
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SOJEME
  • MEMBER
  • 3 POSTS
Please help! Each time I park my car for about six hours the battery normally goes flat. I dont know how to trace whatever kills the current. The alternator works quite well. What I now do is that whenever I know I will be parking for long, I simply disconnect the terminal and in that case, the car starts when I am back. But whenever I leave the battery connected, it suddenly dies until I borrow one to start it before putting it back. Thanks.
Jan 24, 2009 at 12:51 PM
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DOCHAGERTY
  • ✓ASE Certified Mechanic
  • 9,606 POSTS
  • ASE Certified Mechanic
A key off draw big enough to cause what you are claiming should be something like a light left on or an aftermarket sound system or alarm system. Using an ammeter to find it, installing it in series with the battery and pulling fuses until it goes to less than 50 milliamps, would be how I would find your parasitic draw. Let me know what you find.
Jan 24, 2009 at 3:38 PM
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