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Old 01-27-2013, 05:18 PM
crhodes435 crhodes435 is offline
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Location: Haverford Pa
Join Date: Jan 2013
Posts: 6
Mein Auto: 2000 740il
So I was able to do the parasitic draw test thanks to the instructions I got here. There is no parasitic draw on the battery after the car goes to "sleep". I did unlock the dash panel and saw that the alternator is charging correctly at 13.8 most of the time. It drops a little at idle when I use the brakes but not below 12. I am wondering in there is something drawing too much power when the car is running and that is whats causing the issue. Last night I had to drive home about 40 miles in FAIL mode and the lights never dimmed or anything like that even at an idle. I charged the battery over night and the issue went away. But I was driving it again today around town and it happened again. If there was a circuit drawing too much during normal operation the fuse should pop so I'm not really sure where to go from here. Should the car run on just the alternator with the lights on? I started the car and disconnected the positive cable and it kept running but when I turned on the lights it died right away.
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