Battery Draw

Discussion in 'Electrical Systems' started by 2000z, Nov 28, 2020.

  1. 2000z

    2000z Member

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    I've been trying to track down a 280 miliamp draw on my battery. With the multimeter between the negative battery cable and the battery post I pulled every fuse in the car and the draw never went away. I unplugged the the 2 pin connector on the alternator and the draw went away. It should be noted that I just replaced the alternator and the one I replaced was in the car less than a year and died. Any idea what would be causing this?
     
  2. badazz81z28

    badazz81z28 Veteran Member

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    When the engine is cool....is the alternator warm?
     
  3. tom3

    tom3 Veteran Member

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    This car have an amp gauge or a "gen" light?
     
  4. 73 Z

    73 Z Veteran Member Gold Member

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    You've narrowed the problem, must be between alt or wires to alt circuit/gauge
     
  5. Twisted_Metal

    Twisted_Metal Administrator Staff Member Lifetime Gold Member

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    Sounds like a faulty diode in the alternator is causing the draw.
     
  6. carhead22000

    carhead22000 oldblue

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    alternator.
     
  7. CorkyE

    CorkyE Veteran Member Lifetime Gold Member

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    Agree with Twisted. You can buy rebuild kits and YouTube has several videos on how to install.
     
  8. mallard

    mallard Veteran Member

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    My guess as well.
     
  9. 2000z

    2000z Member

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    I found the problem and it wasn't the new alternator. Looks like the previous owner half assed a 1 wire alternator install and then swapped the 3 wire back in before selling the car. I recently cleaned up the wiring in the car and one of the wires for the 2 pin connector on the alternator was mangled inside the electrical tape around the wires. I replaced that wire and once that connection was good again that plug was getting 12V straight from the battery. I pulled all this wiring and I am going back with a new 100 amp 1 wire alternator with a new wire. Since I also went EFI the 100 amp alternator is probably a better idea over the stock replacement 63 amp from the parts store.
     
  10. a73camaro

    a73camaro Veteran Member

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    You can remove the positive wire from the alternator and confirm that the draw goes away.
     

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