The Stovebolt Site Forums The Shop Area The Electrical Bay hunting a parasitic leak

A friend has a battery drain,not alternator,fuses wont stop it ,read how to measure it for size then hunt for it that way. Any suggestions it's an 80's chevy short bed??

Pull all the fuses one by one and leave them without replacing them until it's found or until all the fuses are pulled.

Does that truck have the OBD I rudimentary computer and sensors? I had a module on an '88 Dodge Dakota do a similar thing.

Otto thanks for quick reply -have to look at it again,is my pastor will see him this morning. Hdn't thought of a computer leak,gonna wear his hood hinges out. Will get a year,think it's a V-6 is chevy.

Otto that truck with parasitic leak is a 93 if that tells you anything,i've had all the fuses out one at a time,maybe I need to leave them all out as I go. Maybe a backfeed ??

Yes, I would pull them one at a time and leave them out as you pull the next ones down the line until you see a change on your meter.

1993 probably has the rudimentary computer that runs stuff like throttle position sensor, etc. There will be a main computer module somewhere.Sorry I'm not very familiar with vehicles built after about 1979.

Check the ignition switch, too. If it's got slop in it it might be staying on ACC or ON even with the key pullout out. My brother drained his battery last week on his '69 GTO with the ignition key on the steering column.

It's sloppy/worn out or whatever and the key came out when the switch was in ACC position instead of OFF.

Otto Thanks for the ideas on this one I would guess that ignition switch is original and well worn.

Wiring Diagram 1993
http://67-72chevytrucks.com/vboard/showthread.php?t=465888&page=2
The wiring diagram is sectioned by areas. Easy to print but a pain to use.

It's not easy troubleshooting wiring harnesses with plugs and sockets.
Do not force a plug or socket to disconnect. They usually have a clip or retainer that needs to be pressed or guided.
Check areas first that are easiest to access.

Has anything electrical been added lately?
Has there been a recent damage or wreck that may have damaged wires?

Just reading the posts about phantom leaks---my dad had a similar situation once on his car. Everything off, car sets for a few days--battery dead. Hunted down everything we could think of, to no avail. Happened to walk by the car one night & noticed a dim glow in the dash. Lo and behold, the dang glovebox door was not shutting all the way and the light was on. We never saw it in the daylight, but at night there it was. Fixed the glovebox door and solved the problem. Just saying. .. .

My father wired his volt meter to be hot all the time... it was enough to draw the battery down. I fixed that and no more dead battery!