Topic: battery runs down
in Forum: C3 Electrical
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Still more electrical problems. I finally have all the electrical problems on my 78 Pace working or so I thought. The last problem I repaired was the dome and under the dash lights. Since I fixed the problem the battery runs down if it sits for more than two days. The battery has been checked twice and the alternator works. I measured the current the interior lights draw and it is around four amps when they are on (these lights have a delay before going off) then the current draw drops to less than can be measured. The only thing on the vette I don't have working now is the factory alarm, could this somehow be connected with the battery problem? I also need a schematic of how the factory alarm is run on a 78 vette.
Thanks
annicorvette

Thanks
annicorvette


Annicorvette
Lifetime member # 35
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annicorvette,
I can't help you right now with a schematic, but I really don't think the factory alarm is part of your problem. If you can't get a reading on your voltmeter for a voltage drain, then I would have to say that your battery is starting to go bad. If you have a short or draw in the electrical system, it would usually show on a meter.A car that is stored for the winter months or hardly driven has a tendency of shortening the life of a battery. Here is a couple ways to check out your battery:
Take the battery out of the car, charge it up and have it "load" tested.
Or the other way: Charge the battery up (out of the car). Take a voltage reading, leave it sit for a day, then check the voltage and see how much it lost. If it goes down to 10 volts or less then the battery is no good. Lets us know what you find out.
Reguards, Sarge
I can't help you right now with a schematic, but I really don't think the factory alarm is part of your problem. If you can't get a reading on your voltmeter for a voltage drain, then I would have to say that your battery is starting to go bad. If you have a short or draw in the electrical system, it would usually show on a meter.A car that is stored for the winter months or hardly driven has a tendency of shortening the life of a battery. Here is a couple ways to check out your battery:
Take the battery out of the car, charge it up and have it "load" tested.
Or the other way: Charge the battery up (out of the car). Take a voltage reading, leave it sit for a day, then check the voltage and see how much it lost. If it goes down to 10 volts or less then the battery is no good. Lets us know what you find out.
Reguards, Sarge
TKO500 5 spd.
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Born 8/1981
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Castle Rock, CO - USA
Joined: 4/21/2002
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Vette(s): 1973 T-Top
1993 Coupe
Sarge is right. If your static draw is near nothing, then the problem is internal to the battery. Over time the battery sulfates and and the plates short together, causing the drain.
Alex

Alex

By all means, change the wiring. I bought mine, drove it home into the garage,blocked it up to work on the brakes (of course) and was an eywitness when the old rotten wires shorted out on the alternator and gave me a fireworks display. If the hood had been closed it would have burned the car. I knew the wires were bad, but didn't know how bad. It's amazing what a brand new battery will do.
I put a new harness on it and feel much more secure.
RonC72
I put a new harness on it and feel much more secure.
RonC72

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Hi,
Have you checked the alternator output? There are 2 listed for your vehicle as well as mine (82). I went to the larger 120amp, a new battery and new cables and resolved the problem of the battery going flat every night. The cables are important primarily because of the length they have to run and the corrosion that builds up inside the plastic sheathing-the resistance goes up, the amount of amperage going to the battery goes down. Now if it would just warm up and stop snowing I could actually drive it!
Good luck!
Craig
Have you checked the alternator output? There are 2 listed for your vehicle as well as mine (82). I went to the larger 120amp, a new battery and new cables and resolved the problem of the battery going flat every night. The cables are important primarily because of the length they have to run and the corrosion that builds up inside the plastic sheathing-the resistance goes up, the amount of amperage going to the battery goes down. Now if it would just warm up and stop snowing I could actually drive it!
Good luck!
Craig

in Forum: C3 Electrical
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