Battery drains quickly-Where do I start?

[sweet97]

I thought my battery as bad because 1 hour with the door open and the battery is dead. Had the local Advance Auto check it and the alternator and battery came back good. After having it drain several times they replaced it. Put the new one in and it started right up. Took a 5 mile drive and parked it for 2 hours. Dead!! Electrical work is my poorest forum. Where do I start. I do have a continuity tester with the lighted handle/probe. Nothing is new. The first battery sat all winter and lost most all it's acid and I thought that was it. Is there anything common to these cars that may be draining the batteries? Thanks, Mark
PS: With the key off should the tester light with the clip on the positive terminal and the probe touching the motor/ground? mine does. Thanks again.

 

[RotaryKnight]

first, get a volt ohm meter, or a multimeter from any electronic store.

Shut the car off and dont turn any accessories on.
Select volts from the multimeter and take the two probe wires and touch the positive to the battery and the negative to the cars body (anything metal).
If it shows more than 500mv than something in your car is still on.
Usually when you do this test the drain should only be around 1mv-10mv, and thats mostly from the clock on the radio.

So the next step would be to go the the fuse box and check those fuses for where the volts are comming from.

 

[ndilo21]

The answer to your question is yes. All you are doing is closing the circut and the light should light. If you connect one end to your battery clip and the other to the battery terminal, there should be little to no light. If you have a bright light, which you will, one way to test w/o an ohm volt meter is to start pulling fuses until the light dims or goes off. When the light dims of goes off, you know which circut the short is on. Then you need to search all the wires in the circut.

 

[Nanan]

Do you have aftermarket radio and or amp? They tend to drain power if not connected correctly.

 

[sweet97]

Thanks so much for all of the tips! I found a friend last evening that had keys to the shop where he worked and he put the battery tester on the battery which is new and when he applied a load it just stopped the car from running, just died. Seems the new battery could be bad? I will take back to the store for more testing. No added items to drain the battery. Battery over winter lost most of it's acid and would die easily so it was replaced and still trobule. I will update when I get back from the store.Mark

 

[napkinthief]

A stripped wire near the metal of the chasis can drain the power.

I had a problem with the trunk light on the driver side near the rear wheel. It would not go off, the fuse was too big for it, just replaced it with a 10 I think. Was a 30.