rob_engineer

A good battery should read at least 12.8 volts. If it is less than 12.6 volts then there is a very good chance your battery is bad. If it's below 12, then almost certainly is bad.

rob_engineer

Kind of true, but not really. Good batteries under no load will read at least over 12.6 volts. If it's reading 12.0 you got real problems, unless you left something on that is draining it.

Jeepstin12

I installed this little $5 voltmeter in my rig after experiencing the dead battery. Probably one of my favorite cheapo mods to date. The 11v is ignition on, no running engine and the 13v is engine running, ac on, lights and done light on. Not that it helps when the batt is dead but peace of mind when running lights, winch, etc. I also bought the Li-Poly battery pack that can jump your vehicle. There are three brands available. Can't recall which mine is but a good option for $125 vs. installing a second batt. Particularly when I want the genesis kit, which done right, by their recs, will run about $1g.

rob_engineer

I think your calibration must be out. Not running should be 12.6 - 12.8. When running it should read around 14.3 ish. When I had a motorhome I installed a separate digital voltmeter so I could monitor the batt levels when dry camping.

Jeepstin12

it will hit 14's when driving, lights out, etc. I'm not particularly concerned for absolute accuracy, as long as I have an approximate. Which most people deal with on analog vs. digital. And, for $5, I didn't expect perfection.

Collyn

Took mine out the day I bought it. Mine is an April '12. Put the battery in my sons car and it lasted about a year. He has a Hyundai Elantra and a small alternator. The stock battery is not exactly a great battery. It is barely sufficient for getting the Jeep off the dealers lot. Add some accessories and it's gonna be a short lived part.

demp

Just lost my factory battery this evening. Cranked fine to pull out of the garage so I can put the top up. Could not get it to crank to pull back in......

I've noticed a few weak starts but never anything worrying. I would have had this one for 2 years in just over a month. I guess my plan to get a better deep cycle has advanced in schedule

rob_engineer

I'm happy with the Walmart Maxx everstart I put in yesterday. I forget the number, but it has a nice increase in cranking amps compared to the factory battery. Price was nice and it has 3yr full replacement warranty. Just wondering, are you outside the factory warranty for the jeep? If not, wouldn't they be on the hook for replacing the battery?

Scrappi

So glad I saw this.. My 2012 JK battery died last week with No warning. $175 later, new battery. I See a pattern here.

Jeepstin12

A friend of mine actually had the dealer replace his under warranty.