Once again...more car woes (electrical)

Discussion in 'After Hours Lounge (Off Topic)' started by Tim Hoover, May 20, 2005.

  1. Tim Hoover

    Tim Hoover Screenwriter

    Joined:
    May 27, 2001
    Messages:
    1,422
    Likes Received:
    0
    The other morning, I went out to start my 5.0 Mustang and the battery was completely dead. So, I went out and bought a new battery. The next morning, THAT battery was dead as well. I've borrowed a charger from my neighbor and charged them both back up, but something keeps draining them after installation into the car. I've thoroughly searched corral.net for advice on this, but have come up empty-handed. My multimeter shows no current draw between the negative terminal and body ground (with a fully-charged battery), and I've also performed continuity checks for shorts between the same two points...removing every single damn fuse and STILL showing continuity. All this has been done on advice from corral.net, and I'm still getting a serious battery drain. Any ideas?
     
  2. Joey Skinner

    Joey Skinner Second Unit

    Joined:
    Sep 12, 2003
    Messages:
    339
    Likes Received:
    0
    Maybe the alternator? Try disconnecting the hot wire and recheck.
     
  3. Eric Kahn

    Eric Kahn Guest

    to do the current draw test, you have to disconnect the negative battery terminal and do the test from the battery post to the disconnected negative battery terminal
    all modern cars will have some milliamp draw for the computer memory and the radio memory
     
  4. Tim Hoover

    Tim Hoover Screenwriter

    Joined:
    May 27, 2001
    Messages:
    1,422
    Likes Received:
    0
    Corrected my current-draw test, and still nothing. Zero. I did discover something interesting, though...with the battery cables off, the battery shows 12V as it should. As soon as I connect both cables, the voltage across the battery terminals drops down to 8.3V. Trying various things out, I unplugged the wiring harness on top of the alternator and suddenly the voltage across the battery terminals with both cables connected goes right back up to 12V. I'm presuming that my alternator itself, or at least a part of it, is faulty...
     

Share This Page