Angry_Fisherman

Went to start it up this morning and it started to turn over but died and could not get it turn over, no clicks no lights on the dash. I tried to turn on my 2 meter radio which is wired direct to battery and the display flashed on/off very quickly. I don't think the 2 meter radio killed the battery because even if I had left it on, it has a 30 minute automatic power off.

12 hours prior it started just fine, did not hesitate to start or turnover slow and I drove home about 25 miles no issues.

Called AAA and he jump started it but it died as soon as he disconnected the portable battery jumper. Jump started again and same result. He checked with his tester and said that we were getting 14.2V at the battery while it was still running. This is the original OEM battery.

Is there some other underlying issue possibly or should I just go out and buy a new battery or should I leave it on the charger over night and see if we're in the clear.

I don't want to tow it to a mechanic for a dead battery and I don't want to buy I a battery if that is not the problem.

tkelly311

1. What year is your Jeep?
2. How old is the battery?
3. Is there any corrosion on the battery terminals or the starter? Are the battery cables nice and tight on both ends?
4. Is your Jeep an automatic or a manual?
5. Did you try starting it in neutral or, if automatic, try in neutral or shift out of park and then back to park and try to start it?
6. Would your headlights or taillights come on?
7. Can you get another battery that is close in spec to yours that is confirmed good or try your battery in another vehicle with similar spec battery?

Vladimer

Sounds like the alternator is not pumping any juice into the electrical system to charge the battery. I'd check if any of the leads to the alt have been cut/severed as a quick once over or have the alt tested. I say this because once the battery pack is disconnected the vehicle runs on the alternator and not very dependent on the battery.

Hopefully someone more experienced on it will chime in.

Angry_Fisherman

I'll have to do more troubleshooting when I get home. I was already late for work so once it was determined that I can't just jump start it, focus was shifted on how to get to the office.

1) Jeep is 2011 (purchased in Feb 2012
2) original OEM battery
3) No corrosion, battery cables are nice and tight
4) Automatic
5) only tried to start in park
6) haven't tried headlights or taillights yet
7) only have 1 car so no extra batteries

Mark Doiron

Good voltage reading while running is what I understood you to write. What was voltage reading when not running? Regardless, take battery to local auto parts store so they can load test.

Huk

Once again I am following a post from Mark... I have had the same issue - good one day and dead the next. The battery shorts/dies suddenly and won't let the jeep run on its own. Since your alternator seems to be working - I bet If you kept the pedal to the floor it might make enough juice to keep running. Then die as soon as you let off. At least that was the case for me. So here is another vote to test battery. Good luck.
Editing
I meant that the high rpms allowed the alternator to overcome the battery issue - not that you should run without battery or that this would get you driveable.

Angry_Fisherman

I just checked the voltage on the battery after it's been sitting all day and it's at 6 volts. I don't think even if I got it started I would even be able to get back home from the auto parts store with a new battery. I'm going to head out in a bit for a new battery and hope that is the actual issue.

ronjenx

The JK won't run on just the alternator. If the PCM detects too low a voltage, or no voltage as when the battery is disconnected, it will shut off the generator field.

Your JK starts and runs when the jumper battery is connected, but will shut off as soon as the jumper battery is disconnected, due to the battery being discharged.

Take the old battery out, and connect a known good battery, (not one that is still in a jumper vehicle), and read the alternator voltage while the engine is running.

tkelly311

+1. Any major auto parts retailer will test the battery for free. Most likely low voltage from the battery. Speaking as a person that works PT at an auto parts retailer, if you buy a battery and have them install it in the parking lot and it doesn't fix it, they should allow a return. That being said, since it's 3 or so years old and it's possible depending on the conditions it's exposed to like climate, temperature changes, dry & hot the battery's life can be shortened. Possible the cells are drying out, has it sat without being started for extended periods of time, do you have any aftermarket accessories running off of it, if so, how are they connected? These are some of the factors that can shorten a batteries life. The internal connections can get damaged or loosened causing bad or no connection which can have symptoms like low voltage. Overall, time to try another battery.

Angry_Fisherman

When I opened the hood to swap out the battery, I noticed a rotten egg smell. While I was pulling it out I could feel that it was swollen. This could be a symptom of a faulty alternator overcharging the battery but I'm going to keep my fingers crossed and hope that replacing the battery has resolved the issue.