Strange Battery Drain

[Groundhog]

Have any of you guys, or gals, seen this before?

A friend of mine parks his Jeep, lets it sit for a couple days and when he goes to start it, the battery is totally dead. We disconnected the aftermarket alarm, door locks, stereo - almost everything we can think of that draws juice. No luck. We even checked the ignition switch to make sure its not screwed up, and it's not. The battery is brand new, second one.

Any ideas?

 

[Pickle]

This is called a parasitic drain.  What year is the jeep?

 

[RobTJ]

The cold weather will effect a weak battery.

 

[beaker]

did you try disconnecting the battery?

It may be new, but that does not guarantee it's good.

Grab a ohm meter, disconnect the battery and start checking for low resistance to ground on various circuits.

Remember to disconnect the battery or you'll need a new ohm meter.

 

[CrzyFrlssJeep]

If you don't have a test light, get one and connect it between the postive terminal and battery cable.

1. Make sure the doors are shut and key is off as well as everthing else.
2. If it's lit you have a drain going on.
3. Pull the dome light fuse or stick a tennis ball between door and light switch.
4. Start pulling out fuses til' the test light goes out. (a friend can help here)
5. Whatever is on the circuit that made the test light go out is where your problem is. (look in the owners manual)

Good luck, and check that battery out too.
Just because it's new does'nt mean it's good. (I've seen NEW dead batteries before)

 

[TJ]

got the same problem in a 91 dodge cummins truck I was told after checking the fuse block to check the unfused relays :zbanghead:

 

[Groundhog]

Not sure on the year. I think he said it was a 98 GC.  Anyway, I told him I wouldn't look at it until PEP boys load tests and replaces the battery if it needs it. I've had brand new batteries go bad right out of the box myself so I want to eliminate that right off the bat.

The test light procedure sounds like the best way to go, so that's what I'm going to suggest when he brings it over. I'll post results as soon as I can.

Thanks all.