Battery drain
Thread Starter
Le Mans Master
Joined: Jan 2006
Posts: 5,921
Likes: 0
From: GA "When I grow up, I'm gonna get a Trans Am and run from the cops". Direct quote from my 4yo son.
Battery drain
Not my Corvette, but my '69 Camaro. If I leave the battery hooked up it will go graveyard dead overnight. I have an Optima battery which holds a charge just fine even over long periods if not hooked up. My guess is the voltage regulator. To my understanding there are two types, one being mechanical and the other electrical. Again what I've heard is the mechanical one has a "gate" in it that is prone to sticking and putting a drain on the system. Do any of you guys have any knowledge regarding this? I've dealt with the problem for a while but just keep the cables off when not in use. It was not a gradual problem or anything, just happend like overnight. Hopefully I'm on to the problem as it is an easy fix.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
The voltage regulator is a possibility but don't count out anything else just yet.
Have a test light handy. Disconnect the negative battery terminal, and put the test light inline between the disconnected battery cable and the negative terminal. The bulb will light up if you have a draw.
Now, start pulling fuses one by one, until the light goes out. If it goes out after you pull a fuse then that's your trouble circuit.
If it doesn't go out you'll want to look to things like the voltage regulator, and system relays that have 12V constant.
If you suspect that voltage regulator, disconnect it, and see if the test light bulb goes out.
Have a test light handy. Disconnect the negative battery terminal, and put the test light inline between the disconnected battery cable and the negative terminal. The bulb will light up if you have a draw.
Now, start pulling fuses one by one, until the light goes out. If it goes out after you pull a fuse then that's your trouble circuit.
If it doesn't go out you'll want to look to things like the voltage regulator, and system relays that have 12V constant.
If you suspect that voltage regulator, disconnect it, and see if the test light bulb goes out.
Thread Starter
Le Mans Master
Joined: Jan 2006
Posts: 5,921
Likes: 0
From: GA "When I grow up, I'm gonna get a Trans Am and run from the cops". Direct quote from my 4yo son.
Thanks Matt, I'll check it tomorrow. I won't have time tonight. I'll let you know what I find. Do you know about the two types of regulators or is that just some bad info I picked up somewhere?
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Burning Brakes
Joined: Feb 2004
Posts: 924
Likes: 2
From: Kearneysville West Virginia
If you have an external voltage regulator, then it most likely has two relays in it and you could very well have one relay stick and that would drain the battery. An easy test would be to pull the multi wire connector on the voltage regulator and see if the drain goes away. Of course, you could have something else causing the drain, such as a light, accessory, etc.
Thread Starter
Le Mans Master
Joined: Jan 2006
Posts: 5,921
Likes: 0
From: GA "When I grow up, I'm gonna get a Trans Am and run from the cops". Direct quote from my 4yo son.
If you have an external voltage regulator, then it most likely has two relays in it and you could very well have one relay stick and that would drain the battery. An easy test would be to pull the multi wire connector on the voltage regulator and see if the drain goes away. Of course, you could have something else causing the drain, such as a light, accessory, etc.
I'll post back tomorrow or the next day when I have time to fool with it.
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
There are 2 kinds of regulators: Internal and External, a 69 should have an Internal I believe. If its an external it will be a black box up front there kind of cose to the alternator. An Internal will have no box, and a 2 wire connector on the side of the alternator. If you have a drain and you suspect the alternator, put a test light between the + cable and the + battery terminal/ With everything off it should not light up. If it does there is a problem, disconnect the alternator and see if it goes away
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