2001 BMW Z3 Charging

2001 BMW Z3
52,000 MILES • 6 CYL • 2WD • MANUAL
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RUDY A
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Thinking that I had a dead battery after not holding charge I repaced it. A few days later new battery dead also. Charged battery and removed pos. cable, battery held charge. Disconected cable at alternator and charge held for over 2 weeks until I reconnected alt. cable. Replaced alt. lost charge overnight. Had old alt cheched out and tested OK.
I'm lost
Any ideas??
Thanks
Rudy
Aug 30, 2010 at 10:38 AM
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DOCHAGERTY
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Where did you source the replacement alternator? Where did the old alternator receive the test?
Aug 30, 2010 at 5:51 PM
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RUDY A
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The new alternator was apudrchased from a reputible recicler. The original was tested by an electric auto shop on a machine
Aug 31, 2010 at 4:43 AM
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DOCHAGERTY
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If there is a key off draw, it needs to be found. And it may or may not be the alternator. The car has to go into a sleep mode, this can take up to 16 minutes. Measure the key off draw, all lids shut and ammeter in series with the battery. It should not exceed 50 milliamps. This could be the car not going to sleep or a door lock actuator keeping the bus communication active and not allowing the car to enter its sleep mode.
Aug 31, 2010 at 8:30 AM
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RUDY A
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Re Battery Discharging 2001 BMW Z3

Ampmeter in series drawing 97 milliamps
No trouble codes
2 cables at pos. battery, larger no draw smaller 97Ma
Sep 10, 2010 at 12:26 PM
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DOCHAGERTY
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Pull fuses one at a time to see if the draw goes away. Is there any after market add-ons?
Sep 11, 2010 at 4:07 AM