This past week my car has had a weird draining problem, I have no idea what it could be, let me describe it.

When the car is running the battery gauge reads 13v right in the middle, and everyhting works fine, but the second I turn off the car, and I put it in the on position, it reads the voltage at the first quarter mark, and when I try to turn the car on it will barely crank..

I cleaned the contacts up on the battery and the wires really good. but that didn't help much, what can be the cause of this drain???

Any help will be appreciated.

Oh yea, I also took the battery out of the car to see if it was drained, but the trickle charger read 75% full?????

 

first you should check battery voltage with a volt meter it should read 11 to 12 volts. if not take one of the cables off see what happens, if it goes up somethings draining the battery, if not the battery is probably bad.

if its 12 volts with the cables connected you probably have a loose connection or ground.

 

Terminal voltage and load test are first. Next place a current meter in series with one of the battery leads. U can use a test light if you want. Normal standby voltage with key off, doors closed hood light bulb out should be less tha 500ma or one half amp or less. If you have a drain pull fuses out one at a time until the drain goes away. It's all very basic troubleshooting. If that fails disconnect the alt as they in rare cases can do that.