Just read it with a DC voltmeter, I have a Fluke 87 multimeter, however it's not a $15.00 meter. But as I also posted, I read good voltage on the battery even though the battery would not start the Jk.

 

Batteries are a lot more than just volts though! For example I install 24v fire alarms in buildings (2 x 12 volt batteries wired in series are the backup supply). When ever I service an alarm we check the batteries. The majority of the batteries are 12v 7Ah (amp hours) the bigger the system the more ah a battery needs, so a car battery will be much more than that. Quite often a battery will read 12v on my meter but the amp hours are far below 7, meaning the battery is no good.

So what that means is that the internal capacity of the battery isnt there. So when you hook a volt meter up to a car battery it is misleading. It may say 12v but you arent checking its capacity. So when you load test a battery what it does is put the battery under stress to make sure it still has the capacity to crank the Jeep.

Please correct me if im wrong but I think I got it after working at a shop for 5 years and doing what I do now for another 5.

 

That is very good, for autos we use a very special device that costs over 700 dollars just to test for how many cold cranking amps the batt has available. CCAs are what tell you how well it will spin the engine over. If you don't have many CCAs available when you hit the starter then the starter won't spin at all or not fast enough and also the volts that appeared to be there with your little volt meter will drop so low that they system may reset due to the voltage dropping below 10.5 volts. A voltmeter alone just can't tell you how good your batt is.

 

You are exactly right, you have to do a load test to know if your battery is any good. A volt meter will only tell you what voltage is in your battery, it will not show you any other problems unless you have a plate welded together or a serious problem. Load tests will tell you if your battery is holding up when you are putting it to the ultimate test (starter). It will also show you if your battery is on the way out (will drop too many volts when put under a load).

 

to the OP!
you mention that you also have CB, PIAAs and WARN lights
SO...
Why not investing in a "Dual Battery System"!?
Brake the loads off your Battery, one Battery for your Jeep and one for your accessories!

 

Money constraints right now.

 

A dual set up is a great idea however, I dont see these three mods requiring a dual set up. A CB doesnt pull that much power. There are only two sets of lights chances are they arent used that much and when they are used Im willing to guess the vehicle is running so it wont strain the battery as much as... well lets say ECHO's rig who probably lights up half of the east coast when those switches are flipped. I dont feel that a dual set up is needed for what the OP has, would it be nice? Yes but not needed.

Seriously just have your battery load tested and put this thread to rest.

 

Hook it up to your battery and crank the engine. If your readings dip below a certain point as your battery cranks the starter, your battery has a problem (check both amps and volts).

Sometimes a batter no longer has the cranking power to crank the starter despite showing the proper voltage on the meter. It'll show the correct voltage, but can't turn the starter over. That's why you must watch the meter as you crank the starter. If you crank the starter and you show the correct readings, but it still won't turn, it's your starter (or a connection to your starter) and not your battery.

It's been a while since I've done it though, so I might be leaving out some details, but I think that's about right. Anyone want to chime in in case I'm missing something?