what the hell is drawing voltage and draining battery

[txgunrunner]

my battery goes dead after just 2 days of no use. power was off to everything and i pulled every fuse and put it back in and watched for an arc. the only fuse that arced was the parking lights, if he lights were off why would it do this. is there anything that is tied into this fuse that is staying on and drawing power? i have an aftermarket radio but its not tied into this fuse. thanks for the help

 

[HISSIN50]

Parking lights are always hot, as I recall.

Good luck.

 

[Daggar]

Bad diode in the alternator's voltage regulator would be my guess. The alternator will operate normally when it's being rotated and act as a very inefficient motor (powered by the battery) when the engine is off.

 

[txgunrunner]

bump

 

[88GT17MA]

Bad diode in the alternator's voltage regulator would be my guess. The alternator will operate normally when it's being rotated and act as a very inefficient motor (powered by the battery) when the engine is off.

I'd look into your alternator also, check all your main wiring (grounds, + to alt., etc.). Something could be loose/corroded or even disconnected for that matter.

 

[SamSnyder]

A buddy had a maladjusted interior light switch on the rear hatch that left the lights on inside killing his battery.

 

[mjbtv]

Disconnect the negative battery cable. Run a test light between the battery cable and battery post. If test light lights you have a 12 volt draw. Start pulling fuses untill the test light goes out. That will be the circuit that needs repair. I once had a short at the cigar lighter that caused the same problem.

 

[jrichker]

A buddy had a maladjusted interior light switch on the rear hatch that left the lights on inside killing his battery.

This is very typical of the sort of parasitic drain that kills batteries.

Typically it is something draining the battery. Small things like glove box or courtesy lights are often the culprits. If you have an aftermarket stereo or alarm system, it is also suspect.

The ideal method is to disconnect the positive terminal, and connect a Digital Multimeter (DVM) between the positive terminal on the battery and the positive cable. Set the DVM on a low current scale of 2-5 amps if it doesn't auto range. Watch the current draw, and then start pulling out fuses. When you see a sudden drop in the current, that circuit is the likely culprit. Note that the computer, radio & clock will draw less than 1/10 amp to keep the settings alive.

See http://assets.fluke.com/appnotes/automotive/beatbook.pdf. You will need the Adobe Acrobat viewer which is also a free download – http://www.adobe.com/products/acrobat/readstep2.html

 

[kfellers]

Be sure to check the courtesy lights in the sunvisors if you have them. That's where I believe I had my problem. The mirror cover in the sunvisor was too worn to make contact with the switch to turn the light off.