Battery went dead after truck sat for 2 days.

Charged battery and it went dead overnite.

Charged again and its staying charged after driving it 60 miles.

WTF???????????????

 

Something is drawing power. There are three basic possibilities:

1. Something was left 'on' electrically in the truck. A light (unlikely, because they probably time out), door ajar, something plugged into the unswitched 12V power receptacle, something plugged into the always-hot line in the trailer wiring, etc.
2. Something has shorted out (wiring or a component) and is drawing power from an unswitched power source.
3. The battery has shorted internally. This happened on our 2005 Grand Cherokee when it was only about 13 months old.

#1 you can check for yourself to verify that the situation is resolved. #3 you can test by disconnecting the battery cables and then charging the battery. Let it sit overnight disconnected and see how much charge it has in the morning. #2 is the tricky one... probably need the dealer to inspect for that.

Rob

 

I would start with the battery first before you try anything. Chances of something being shorted out are much smaller then the battery having a dead short. However just double check your door jams that no wires are stripped there, thats the most likely place.

I still would have the battery taken to the nearest auto shop for a load test. It might have to sit a night, but they do a proper test that tests the batteries capacity and limits. Thats the best way to see if your battery is failing. If your battery has a failing cell in it, sometimes it will keep a charge and sometimes will discharge almost right away. So put it under load...

 

In AZ it is not unusual for a battery to die in 2 to 3 years. Heat kills them. Since your truck is an 09, have the battery checked. Like another poster stated, start with the battery.

 

Whatever caused the problem - it has corrected itself. Battery remains charged this am.

 

How long did you let the truck run after you replaced it the first time? Probably didn't get enough to put a good charge in it.

 

Same symptoms our Jeep had. Stone dead one morning, charged it up and used it for the day and it worked perfect for another day or so, then came out to totally dead battery again one morning. Came back to life after another charge. Took it to several places to test the battery (dealer and Napa) and it tested fine under load. Finally just replaced the battery because that was the only explanation.

Rob

 

Don't be surprised if the battery craps out again. Like any product, there are just some bad ones. I replaced the battery January 31st this year on our 93 Mustang. After boosting it two or three times, it just wouldn't crank the engine. FWIW, the voltage measured 12.5, but the thing could barely make the dome light glow.

Turned out to be a bad cell and was replaced under warranty.

 

I too have an 09 with the occasional dead battery. There have been at least three mornings now (since new) that I have gone out to the truck and had a dead battery. I am sure it is not a problem with my battery. I think there is some sort of a software glitch that occasionally causes the truck to leave a component powered up after the ignition is switched off. I know that there is a TSB for the RER causing this on some of the early models. I've had it to the dealer all three times for this issue. Dealer can't seem to replicate the problem and has no idea what to do about it.

 

I'm experiencing the same thing now. I was out of town for a week - came home to a dead battery. Jumped it, seemed fine - went out this morning, dead again. I haven't done anything different - internal lights or other hookups. Has anyone figured out a cause? Did a new battery fix this for everyone? Will the dealership give me a new battery?! My truck isn't even 3 years old - stock battery. Thoughts??