Battery Drain

[JayByrd92]

Hello everyone i have a 1987 Pontiac Firebird 4 barrel v8 and have been having a battery drain for a while now i thought it was the radio so i pulled the fuse and nothing changed if anyone has had a similar problem and knows how to fix it or what to look for please help me this problem is very annoying. I hear this is a common problem with GM vehicles

Topic

[BigC]

Thanks for the diagram. Do both door jams work properly, with lighting the courtesy lights? Both courtesy lights should be “off” when the doors are closed. Also, the light switch for the interior lights should be looked at too. Corrosion inside that switch could also be causing a drain. Keep us posted.

[jbone]

Quoted From JayByrd92:

Hello everyone i have a 1987 Pontiac Firebird 4 barrel v8 and have been having a battery drain for a while now i thought it was the radio so i pulled the fuse and nothing changed if anyone has had a similar problem and knows how to fix it or what to look for please help me this problem is very annoying. I hear this is a common problem with GM vehicles

I had a similar prob in my 96 pontiac sunbird.After multiple attempts to figure this out it wasn’t until me an a buddy was driving one night and he noticed the glove box light was on, come to find out it was that the glove box light wouldnt shut off so i took out bulb and no more battery drain..

Hopefully your problem could be this simple good luck….post back your findings..

[EricTheCarGuy]

Cool great start, now all you have to do is isolate the problem by hooking the ammeter up to the positive battery cable and the positive battery terminal, then start taking the bulbs out of the lights in the circuit, you could also disconnect C208 to eliminate the door light switch and the dome light circuit. If the amps drop when you disconnect any one of these you have found the effected circuit. If I were to hazard a guess I would be looking at the door switches and dome light circuit, not a bad idea to make sure that the doors close all the way.

[JayByrd92]

The problem is solved!!!!! turns out it was the cig lighter thanks to everyone that helped especially ETCG for making such an awsome website.

[twiggy]

Thank you for letting us know the result. And congrats on your successful repair.

[spelunkerd]

If you search “parasitic drain” on Youtube, you will find a couple of videos that I made describing how to investigate this, with a DVOM and a home made short detector. For sure, go to a hardware store and get a simple DVOM.

Looking at your above schematic, I would check the cigar lighter and latch lights for a fault. Last time this happened to me it was a coin dropped into the cigarette lighter — often it’s something goofy and simple. You can simplify the task if you can isolate the branch of the circuit it is affecting, but to do that a DVOM is critical.

[Author]

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