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Old 11-15-2012, 10:47 AM
Joeedawg1911 Joeedawg1911 is offline
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Location: Omaha
Join Date: Nov 2012
Posts: 7
Mein Auto: 2002 325i
Originally Posted by joegr View Post
That, plus use a voltmeter (or the dash diagnostic feature) and measure the electrical system voltage while the engine is running. If it doesn't stay between 13.6 and 14.5 volts, you have a charging system problem still.
I saw a youtube video for that. He said go to test 19 then 9. It reads around 12.3 with a fully charged battery. Then the next day when I drive it with a fully charged battery, it dies on me after X amount of time driving. I know it's dying because my light go dim and my airbag light comes on, radio goes dead and same with the heater. The second I park it and turn off the engine it's dead. I take a reading of the panel (test 19, option 9) and it reads 6 or 7. So at some point the battery gets drained.

So I don't know what to think anymore. When I did the battery drain check it showed it was within limits(11 mili amps) but maybe thats not the case. Perhaps there is something draining the battery at night and the charger system isn't working as well? I have the new battery slow charged up. My new plan is to throw the new one in. And when I park the car I'm just going to keep disconnecting the battery. If it stays charged up after a week or two then i'll know 10000000% that the battery is getting drained at night. That's the only thing I can think of for now until the weekend to break into it more.

Side note: Shouldn't the alternator have enough juice to supply power to the headlights WITH the engine running when my battery dies?
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