Hey all,
I have an 01 jeep cherokee. The other day my jeep wouldn't start when I went on break. When I got off work I had someone jump me off and it started right up. Got home and it will only start off a jump. I pulled my battery and took it to advanced and they said the battery is fully charged but when it is connected the jeep wont even try to start and no electrical things work(i.e. radio, lights, locks, etc.)
I've checked all the fuses and relays that have any thing to do with starting or running and they all look good.
I've also checked all my connections and they all look to be good as well.
I've disconnected my amp as well so there are no external draws on the battery.
I just jumped it a minute ago and was getting a max reading on the volt meter inside the jeep along with the check gauges light.

Any suggestions on what you think it could be would be greatly appreciated.
Thanks in advanced

 

Just an easy check. Sometimes a bat term gets a thin hard crust that looks fine, sort of lead color. It amazes me that they can look so good, you reef it down, and still no contact. (I use my pocket-knife on it, the inside part).

"no electrical things work(i.e. radio, lights, locks, etc.)" That stuff would come on with jumper cables if your terminals where not connecting.

 

depending on where you hooked the jumper cables, it still sounds like your battery to me....put a volt meter on you batt. and see what it reads to start with...put a charger on for a couple hours and the check your battery again....leave the volt meter on it and see if the voltage drops at a steady rate...if so you have a bad cell....this is all with the battery dis-connected....poor mans battery test...lol

 

Well from the way I see things there's only 2 possibilities, bad battery (auto part places are not always right...even on simple things) or cable connections directly on the battery posts.

Double check, a multimeter is your friend here!

 

This was it, my post and terminals looked good but I disconnected them and cleaned them with some baking soda, water and a wire brush and its starting up fine.
Thanks for the help guys!

 

Your welcome! happy trails.

 

Alright so I guess its not fixed... Just went out and tried to start my jeep and now its doing the same thing. When I disconnect the battery and reconnect it my lights and everything come back on but when I turn the key from the on position to start everything shuts off and the jeep wont start. Everything stays off until I disconnect the battery again.
Any ideas?

 

battery shorted

 

Did you check the ground?

 

X2 on the ground(s). Hard to get that crust off the inside of a terminal with a regular wire brush. I use a pocket knife, carefully. Or maybe you used one of those battery terminal cleaner brushes? Like a bottle brush. Don't mean to be such a nag, just that I've seen it happen. Bright shiny lead is the goal. And again, if it's jumped and the lights don't work the problem is not your bat or it's connections. Is everything dead, not just stuff controlled by the ignition?

Edited "IS everything..."

 

You battery has possibly internally failed. It can have a loose connection that works for a moment when the battery posts are wiggles, but it'll burn out as soon as any real load is on it. If this is the case do no more except GET RID of the battery. If it has an internal spark due to this, it can and will explode. If this happens, it will destroy lots of things in your Jeep, and possibly destroy your face if you are under the hood while it happens. Batteries are nothing to mess with if they have failed.