transfrmr

Hey guys.

Well, here I am again with the same electrical problem that's beginning to drive me buggy.

The battery drains slowly while the car is off. It'll slowly wear down untill I can't start the car anymore, particularily when it's parked for a couple of days. I installed a brand new fully charged 1000amp (850 Cold cranking) battery about two weeks ago. Since then I haven't had a problem. Saturday night, I had to boost it to get it started, and had to charge the battery which was almost fully drained.

When I check the amperage being drawn by the car (between negative post on battery and ground cable) while it is off, I get the following results:

Storage switch on (powered) (fusebox) : 34 miliamperes of drain
Storage switch off (no power)(fusebox): 21 miliamperes of drain

This has me befuddled though. If I check the DC Voltage from the negative post to the ground cable, I get a reading when i don't think that I should be. The Voltmeter shows me 12.57vdc, when clearly I haven't got a positive source hooked up. If I reverse the leads, i get the equivalent value, but with a "-" sign, telling me that there is indeed a "flow" to the current.

I'm thinking that this indicates that there is a hot (positive) wire grounded to the body somewhere on the car that is finding it's way back to the ground cable and giving me the reading. (anyone have an infra-red heat-sensitive camera I can borrow?).

I've already pulled all the fuses to check for a difference in the amperage draw and found none. I may do the same again, only looking for the 12vdc reading to dissappear between the ground post and cable. I figure that if it's not affected by the fuses, then i have to sssume that the problem happens somewhere leading up to the fuseblock, which will already save me some time.

It's clearly not draining much, so any ideas on where to start? I've picked up some wire loom to protect areas once I've inspected them, and help me clean up a bit under the hood, so a slow inspection of all the wiring is my best idea right now.

I've heard of some tool made to find shorts using a compass, but not sure how usefull that would be with this little drain.


If you have any ideas or suggestions about any part of this, please feel free to offer them, I'm pretty competent, but lack experience and tips are always great to get!

Thanks!

maximase86

iTrader: (24)

Do you have any aftermarket gear hooked up in your car? This would include stereo amps, fog lights, etc. If so, I'd do some checking around. Also, one thing about the fuse box, something aren't ran through that switch, I don't quite remember what, but I don't think that switch will cut everything off. Either way, it sounds like you got a bunch of hunting to do...

S

transfrmr

Yep..

Well, I've pretty much determined that the problem is pre-fusebox. So either the problem is somewhere before it or on a system that doesn't go through it.

It does indeed seem like it'll be a lot of hunting. I'm actually considering going to look at a parts car that apparently has a great wiring harness.

If I get that, I'll start swapping it in and check stuff out as I go along.

For now a simple disconnection of the ground wire while the car isn't in service is my temporary solution while I try to track it down.