2007 Don't start

[mike]

Howdy All,
2007 Liberty, 72,511 miles. New battery last year (5-31-25). Super Start Extreme from O'Reilly's. Yesterday I had to jump-start it, and same thing this morning. Never had a problem before. The new battery is the same model as the old one, that lasted 5 years. No other changes besides the new battery. I'm at a loss. Any ideas?

 

[lfhoward]

Maybe the battery is actually bad. Oreilly’s will probably warranty it for you if it is bad. See if you can charge it up on the bench.

Your Jeep may instead have a parasitic draw somewhere. If you have a multimeter you may be able to figure out where.

Does your alternator charge the battery at 14 volts after you jump start the Jeep?

 

[mike]

It's weird. When I go out in the morning it starts fine. I leave it running for several minutes. About an hour later is when it needs a jump. We jump it with a NOCO Boost Plus GB40. I've put a NOCO Genius 5 on it, the charger light goes to green, turn the key with the charger still hooked up, it needs a jump. The wife then drives it a couiple miles, parks for about a half hour, and has to jump it to drive home. I do have a multimeter (Fluke 77) but I haven't checked anything yet. I used the multimeter to check things out a few weeks ago and everything checked okay. I couldn't do the check where you leave the meter hooked up and crank it, because the Jeep would start every time I turned the key to crank! It's got me scratching my head, for sure.

 

[24turbo]

My wives Toyota has done something similar 2x now about 5 years apart. Changing the battery cured it both times.

I just remembered I had to change the alternator about a month after. It was literally smoking it would get so hot. I wondered if it was overcharging and cooked the battery

 

[mike]

I suppose it could be the battery. It was new 5-31-25. I bought the same brand because the battery I was replacing lasted so long, 5 years. That said, in this day and age, anything is possible.
I used the multimeter (Fluke 77) yesterday. I tried to start it about an hour earlier, no dice. About an hour after I tried to start it, I started taking readings, here they are: While sitting - 9.58VDC. While cranking - ~8VDC. Hook up booster (Noco Boost Plus GB40) - 12.05VDC. While cranking hooked up to booster - 7.95VDC. Unhook booster measure volts while running - 14.5VDC.
We have another car. I'll be using it to go to the grocery store in a few hours. I drive right by the auto parts store (O'Reilly's) on the way to the grocery. I'll probably take the battery out of the Jeep, take it (and the receipt) to O'Reilly's and see what they say. The only problem I can see with that plan is that I leave my wife at home without a vehicle. Oh well. That's probably what I'll do, unless one of ya'll have something else to try!