Battery drainage

[Pa Goose]

For the past couple of days I have had the problem of a dead battery. I charge it and next morning it is dead again. The battery is 3 months old so I doubt it is the battery. When I went out to the car today the battery was deader than a door nail. I placed the charger on it and noticed something odd.
The ampmeter on the charger started by drawing 10 amps which I expected since the battery was dead. After about 15 seconds it dropped to 5 amps. About 15 seconds later jumped back to 10 amps. It has been in this cycle for 20 minutes now and I can't figure out what the problem is. Anyone ever see this on their Vette?

 

[Pa Goose]

It has been charging now for several hours. Still drawing 10 amps and cycling. Inside of the car, I hear a 'clicking' sound towards the rear of the car, sounds like from area behind right rear speaker area. May be a solenoid cycling on and off. I don't know what it could be. ANY ideas ???
I forgot, it is an 81, C3 Corvette

 

[wishuwerehere82]

It sounds like you may have a shorted cell in your battery.

When the charger pulses like that, the voltage regulator on the charger thinks that the battery is charged, then it shuts off and back on if the voltage is not over 13.7V. Have you put a voltmeter on the battery terminals to see what it is charging to?

 

[Pa Goose]

Unfortunately all of my tools are at work.

 

[wishuwerehere82]

What does your dashboard guage say when you turn the key on? With and without the charger on it.

 

[Pa Goose]

Gauge indications are normal. Nothing unusual.

 

[mbwalker]

Unhook your battery from the car and see if it charges normal.

 

[Daryllawman]

If you can get it running......take it to a Auto-Zone or a Avance Auto and they will test the battery, alt. and starter on the car.....its free

 

[Pa Goose]

I took the car up to the dealership this morning to have it checked out. The battery was good as was the charging system. They worked on it for 2 hours and found nothing. The mechanic told me the only thing he noticed was the courtesy lights stayed on a lot longer than normal. They thought that all the wet weather and intense cold last week may have caused a switch or relay to short and after drying out yesterday went back to working normally.
So I went to work and everything seemed fine. Tonight when I got home I stood behind the car for over 5 minutes waiting for the courtesy lights to go out. Then I went in the house to drop off my lunchbox, got a cup of coffee and when I came back out the courtesy lights were still on. I took out the bulbs as I do not know where to disable the circuit.
At least, so far, I think I have found the problem.]
Anyone know where to disable the circuit for the courtesy lights?

 

[wishuwerehere82]

If you take the glove box liner out(about 8 phillips screws), the timer module is on the right hand side next to the inside of the fender under the dash. It's a little rectangular box (2"x1-1/4"x3/4") with a card edge connector with about 6 wires going to it.