1. Registration trouble? Please use the "Contact Us" link at the bottom right corner of the page and your issue will be resolved.
    Dismiss Notice

Battery Drain

Discussion in 'Early CJ5 and CJ6 Tech' started by Johns1967CJ5, May 30, 2018.

  1. Johns1967CJ5

    Johns1967CJ5 Sponsor

    What can possibly be causing a battery drain on this thing ? there are no lights in it. the key was out of the ignition. I get in the morning starts right up. pull it out in the driveway, by the end of the day the battery Stone dead happened to me twice already
     
  2. Oldriginal86

    Oldriginal86 Member

    Disconnect the negative battery clamp, put a test light from negative post to the clamp. Should not light the test light.
     
  3. Johns1967CJ5

    Johns1967CJ5 Sponsor

    Test light lit up nice and bright :-(
     
  4. Twin2

    Twin2 not him 2024 Sponsor 2023 Sponsor 2022 Sponsor

    most likely the Alternator . with test light still hooked up disconnect alt wires
     
  5. Johns1967CJ5

    Johns1967CJ5 Sponsor

    Would than mean a defective ignition switch ? The switch should kill all that ?
     
  6. Oldriginal86

    Oldriginal86 Member

    Good advice about the alternator, shouldn’t be too bright though. Alternator only draws milliamps. If it’s the cause have it checked by a qualified rebuilder, could have a short. Start with the last electrical item installed and work back from there.
     
  7. Johns1967CJ5

    Johns1967CJ5 Sponsor

    It's been rebuilt I'm suspecting I wired the ignition switch wrong. It's all temp right now
     
  8. Oldriginal86

    Oldriginal86 Member

    Alternator has battery voltage on the charge wire at all times.
     
  9. Twin2

    Twin2 not him 2024 Sponsor 2023 Sponsor 2022 Sponsor


    well there you go . with test light still in place . start there
    as to alt . alt has a 12V hot lead (large wire). nothing to do with switch , except the hot wire for idiot light (small wire) is hooked up to switch only ON when in run position
     
  10. Johns1967CJ5

    Johns1967CJ5 Sponsor

    Ok I'll play around tomorrow see what happens
     
  11. SIDSCJ

    SIDSCJ Jeep addict

    If the light didn't light up, the battery would be dead..........
     
  12. OldAdobe

    OldAdobe Member 2024 Sponsor 2023 Sponsor 2022 Sponsor

    If the light is still on after disconnecting the alternator, and if you have added any relays, unplug them one at a time and see if the test light goes out.
     
    ojgrsoi likes this.
  13. timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    Yes - you need to be systematic. You can remove fuses too. Start disconnecting things until the drain goes away. The most recent changes are the most suspicious.
     
    ojgrsoi likes this.
  14. Johns1967CJ5

    Johns1967CJ5 Sponsor

    So when I disconnect the gray wire which traces back to the voltage regulator the light goes out. Reconnect the light comes back on. Then unplug regulator from harness light goes out ??
     
  15. Don't forget solenoid
     
  16. Twin2

    Twin2 not him 2024 Sponsor 2023 Sponsor 2022 Sponsor


    pull alt and take it to local auto parts store
    and have it tested .
     
  17. 47v6

    47v6 junk wrecker! 2023 Sponsor 2022 Sponsor

    Diode bad?
     
  18. Mcruff

    Mcruff Earlycj5 Machinist

    Yes, my truck had a faulty diode, charged fine but when you shut it off you would have a 1.75 amp draw the whole time it was shut off.
     
  19. Johns1967CJ5

    Johns1967CJ5 Sponsor

    Figured it out. Indicator light was hooked up to the switch wrong
     
    47v6, 71CJ54WD, jeepstar and 2 others like this.
  20. Glenn

    Glenn Kinda grumpy old man Staff Member

    Perserverence pays off. (y)