High Current Draw From Battery

[89 MAUI]

Has anyone determined what a high current draw from the battery is caused from?

 

Edited October 10, 2021 by 89 MAUI

[Padgett]

Many things & depends on what the "high current draw" is (ma or amps). Spec is "under 50 ma" and mine usally runs 20-30ma. Is this a convertible or sunroof car ?

 

 

Edited October 10, 2021 by Padgett

[Philbo]

I've never had to deal with this issue, but I have heard a place to start is to measure the current draw and then start pulling fuses until it drops.  Then you know the culprit is something on that fuse.  Just thinking out loud

[Padgett]

Depends on how high the daw. Under 50 ma is the spec. Several amps is often the HVAC module. Is the fan running ?

[Ronnie]

Another good place to start looking or unusually high current draw is the alternator. Bad diodes in the rectifier can drain the battery pretty quick. If you do my tests in the How-To Guides and the current draw is really high, disconnect the alternator -including the big hot wire- and test again. If the current drops down near the normal range you have found the problem.

 

Be careful disconnecting the big hot wire from the alternator so you don't short it to ground. It is hot anytime the battery cable is connected.