Best way to determine a parasitic drain?

[Hans3T]

Hi all,

I am curious what methods may be possible for finding a drain. I will post in greater detail what I've done already when I'm on my computer, but I would love to hear some more ideas on how to test it.

Thanks in advance!

Sent with Tapacrack

 

[08SolarFlareH3]

Start by charging the battery. Make sure key is removed and door is shut. Connect a DMM between the negative battery cable and negative terminal of the battery. It's going to read high for a while until the computer goes into sleep mod and you will see the current draw drop. When you see this your going to want to start by pulling fuses in the fuse box one by one to see if the current draw drops. When you find the affected circuit it will be easier to determine the exact nature of the draw. I believe the excepted current draw is 50ma or less. You may also need to pull relays if you are unsuccessful.

 

[Hunner]

Change the locks so your son-in-law can't get in!

 

[alrock]

:giggle:

 

[4speedfunk]

Unplug all of your add-on electrical devices (lights, CB, Radios, I-pods, winches, alrams, etc.) If the problem goes away...it was one of those. I'de try that first. More often than not, the voltage leak is probably due to an installation problem with some of your accessories. Unplug everything....see if the problem still exists. If that fixes it, start plugging accessories back in, one at a time and drive around for a week or so to see if the problem returns. Do them one at a time so you can be sure to isolate which add-on is the culprit. You might also check to make sure all of your accessories are wired to a switched 12v source. If they are wired to a constant 12v source, they could be pulling current all the time when you don't them to.

Electrical trouble-shooting is the absolute worst. Good luck.

 

[deserth3]

I remember awhile back people were having problems with the onstar module causing their battery to drain. While you're there you can also check the radio, AC controls and 4X4 controls. I'd just unplug them as a group, then if the problem's there plug one item in at a time. Also your review mirror has electronics in it too. Just be patient, you'll figure it out.