Battery discharged fast???

[Diezel501]

:bang: I just took ownership of a '99 4x2 limited... hope to change to 4x4... Anyway, The reason I'm here is this Jeep has killed 2 batteries within 10days. i did not have it at that time, it was my brothers... He is over it, so he gave it to me... I am mechanical, I can figure things out, I can swing a wrench or hammer if needed, I just need a starting point.

[4.3LXJ]

Charge the battery up but don't connect it. See if they retain their charge overnight. Then we can go from there

[Cheromaniac]

Charge the battery up but don't connect it. See if they retain their charge overnight. Then we can go from there

Good call but I suspect that the alternator could be at fault 'cause it's two batteries that have gone dead in a short space of time, not just the one.
If the battery does retain charge while disconnected, reconnect it and check the battery voltage with the engine running and all electrical accessories off. If it's less than 13.0v, replace the alternator and check the wiring from the alternator to the PDC +ive terminal.

[Pinkyman]

You can also check for power draws. Pick up a test light, disconnect the negative battery terminal, and hook the test light to the negative terminal, and the other end of the test light to the negative battery cable end. If it lights up, you have a draw. Start pulling fuses until the light goes out, and you can isolate your problem.

*make sure to pull the dome light fuse or close all doors and the hatch, or it will be impossible to find the draw.

[drakan1908]

Sounds like the body control module isn't going to sleep. My wife's Grand had that problem, went thru two batteries also, turned out being the switch was bad on the rear hatch. Kept telling BCM that the hatch was open. I had to check current draw thru each fuse and then check each thing on that circuit. Got lucky on the second fuse.

sent from a van down by the river

[Diezel501]

I just got it charged, the auto parts store said it is good and 100 percent charged but it was in the last quarter of life. I hooked it up and the jeep started, battery gauge said 14 so I took her for a quick drive and then parked it and removed the terminals so there is no drain from the vehicle. If the battery is good on Friday I will check the Alternator (I just found out it had been replaced in the past). I will try the other suggestions too. I am sure I have a draw somewhere. Most electronics work, Lights (internal and ext), power windows etc, except the radio... I also have a broken tail light - which was filled with water at one time... Thanks for the start gentlemen, we will see where it leads me. I am seriously going to enjoy this Jeep.

[denverd1]

any parts store will check your alternator and battery with it all in one piece. just to eliminate a few things

[nickyg]

X2 on the draw test, Here's a helpful video that helped me track down a draining battery on my daughters VW "bastard bug"

https://www.youtube.com/watch?v=KF1gijj03_0