Battery Drain

My Jeep has been in hiding and so have I. Now I have a problem. I had to jump the jeep to get it started, nothing crazy; however, the battery wasn't holding the charge, so I bought a new one. This time, however, the battery is still draining and I am not sure what the problem is. Any help would be appreciated in allowing me to identify possible sources etc...

Sounds like a short somewhere, check wires. Aftermarket radio? amp? Aux. lights?

PLEASE, always start a thread with year/engine/trans/whatever else you think might be pertinent.

If you have a power radio antenna, find a very quiet spot and put your ear near the fender by the antenna for about a minute - if you hear an occasional sound, the antenna motor may be coming on from time to time.

This happened to me about a year back - the end-of-travel switches that disable the motor when it's done raising/lowering fouled or something, and the motor was coming on every 20 seconds or so for about a second (enough time for the frozen assembly to cause a short that pulled about 1.5A). Eventually it drained my yellow top low enough to kill it and the alternator.

Best thing you can do is put put an ammeter (DMM on current mode) between the battery and the positive cable, then start pulling fuses one by one (PDC under the hood first, then the interior fusebox) until you find the circuit causing the issue.

Johnnie Walker said:

Sounds like a short somewhere, check wires. Aftermarket radio? amp? Aux. lights?

Click to expand...

wouldnt a short cause a fuse to blow?

Not if it's a low current short, like through the aforementioned power antenna motor. Think of a short as current finding its way to ground before performing it's task. While not technically a traditional short, a malfunctioning motor or some other load may have resistance, slowing the flow of current to below the limits of the protective device (fuse) or the wiring. Checking with an ammeter is the best way to start-disconnect clocks or radios with memory, and see if you're still flowing current. Even a few milliamps will make a difference!