Battery drain (Alternator?)
Thread Starter
Instructor
Joined: Jan 2001
Posts: 108
Likes: 0
From: Western Texas
Battery drain (Alternator?)
You guys have always been so helpful. So try this one. My 77 would not start yesterday - dead battery, only about a year old. Did fine a week ago.
Removed and charged, completely drained. Went to reinstall this AM but put my voltmeter in the circuit before completing hookup. I've 12.4 volts across the circuit with nothing(?) on. Found that I could pull the side connector to the alternator and would open the circuit. It is the red(+) wire, naturally, that shows again the 12.4 volts. My circuit diagram (Haynes) is all but worthless.
Any ideas? Someone know a good source for another diagram?
Thanks in advance for any input.
mox 77
Removed and charged, completely drained. Went to reinstall this AM but put my voltmeter in the circuit before completing hookup. I've 12.4 volts across the circuit with nothing(?) on. Found that I could pull the side connector to the alternator and would open the circuit. It is the red(+) wire, naturally, that shows again the 12.4 volts. My circuit diagram (Haynes) is all but worthless.
Any ideas? Someone know a good source for another diagram?
Thanks in advance for any input.
mox 77
Le Mans Master
Joined: Sep 2000
Posts: 6,036
Likes: 2
From: Westfield Indiana
Cruise-In III Veteran
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Re: Battery drain (mox 77)
Forget the voltmeter, you need to use an ohm meter to see how much current you are drawing. Leave ignition off and key out of ignition. Hook the positive cable to the battery and remove the negative cable from the battery. Then hook one meter lead to the negative terminal on the battery and the other meter lead to the negative cable. Note the ohm reading. Start disconnecting fuses one at a time and see which fuse causes the ohm reading to drop. Once you pull a fuse and the reading drops, you have found your culprit. Figure out what all is on that circuit and check those items to see where your short is at. You will have a slight draw if the door to the vette is open because of dome lamp, etc. My problem was the key buzzer. For some reason, it would drain the battery within two days if the car wasn't driven. I just disconnected it and don't use it. One day I might buy a new one. Good luck with your search.
[Modified by sharklover, 11:36 AM 10/7/2001]
[Modified by sharklover, 11:36 AM 10/7/2001]
Race Director
Joined: Dec 2000
Posts: 19,304
Likes: 85
From: San Diego CA
Re: Battery drain (mox 77)
It could still be your altenator/voltage regulator UNLESS it drains overnight with the car just sitting there. If it does, follow the directions given by the previuos poster - must be a short.
