hi, i am having a problem with my 1980 corvette batterys going dead, i charge them up and it will stay charged enough to start the car, but if i let the car sit for 4- or more days the battery will go dead? I have replaced the old battery with a new one and it does the same thing? I am wondering if it is in the brain or modulator for the car? does anyone have any idea what may be causeing this? the car is in exalent shape with only 19550 miles on it. please email me at aboveknee@aol.com if you can help.

You have a drain somewhere in the circuits of the car. Something is turned on, even when the ignition is turned off.

With the ignition off, pull the positive wire off the battery. Put a 12 volt tester between the post and the cable. If it lights up, you have a drain somewhere. Start pulling fuses, one at a time. When the light goes out, that is the bad circuit.

Also, check the grounding point of the negative cable. It is under the car, on the frame under the battery. These are known to corrode.

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you can also pull the fuses one at a time and watch for it to spark as its pulled or replaced with the key off to see whats draining the power.


Tazz


Rat Rods Rule!

I had the same problem with a bronco 2 . the batt would drain overnight. believe it or not the regulator was on the way out, and there was an internal short in the alternator itself wich was draining the battery, go figure, mike

I would suggest you use an amp meter to see what your amperage draw is. Anything over 200mA will cause a std. cranking battery to go dead after a few days to a week of non use. If you connect an amp meter between a battery cable and a battery post, using the meter to complete the circuit, you will see the total draw. Then to identify the circuit that drawing to much, start pulling fuses. If you only get small changes with the fuses, remove the charge wire from the alternator. Remember that clocks, stereo memory's & computers (ECM) will have a small draw normally under 40mA .

Good Luck.

might want to get alternator checked. A shorted positive diode will kill a battery.