Any ideas where to start. 2 days ago something started killing my battery dead overnight. It is charging 13 amps. I am an electrical dummy, but obviously something is running the battery down. Thanks for all your help.
I did check all the lights last night in the dark, nothing on. I guess I will start with the fuse box test, see if anything shows up. I really don't like fooling with electrical, I seem to cause more problems than I solve. Thanks for all the help.
Fully charge the battery and do a load test on the battery. If that checks out OK, check the charging system, alternator. You should be up around 14 volts with the car running and it shouldn't drop much with accessories on like lights, wipers, a/c, etc.
Could be the alternator can't keep up and the electrical stuff is running off your battery.
Whatever it is, it pulled the fully charged battery down last night. I charged it Sunday, drove it to Autozone and had the battery and charging checked, drove it home and left on the charger. This morning it was stone dead. I know there were no lights on last night, one suggested I check the cigarette lighter.
With everything off, remove the negative battery cable, put a self powered test light (without a small battery in it) between the battery and the neg. cable, if the light comes on, there is a draw,, pull one fuse at a time until the light goes out,, that will get you in the ball park to start looking,, Matty man
Keep in mind, the battery is the most unreliable part on your car. Do the draw test like matt said, if you don't see a big draw (bright test light), my money is on the battery. Regardless of it passing any so called test. Battery's don't play by any rules.
I guess this will be my last post on this. I checked the draw on the battery, not enough to even light the test light. Charging 14.8 v with all accessories on. I left the battery hooked up overnight, it cranked up fine this morning. I love electrical gremlins.
I installed a battery disconnect on the negative cable on one of my cars. This car sits in storage for extended periods & the clock light would eventually draw the battery down. Now when I park I just open my disconnect & it now longer kills the battery.
Not exactly a fix for your problem, but a way to deal with it if you can't find the problem.