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I drive a 1996 cheerokee. From day one I had issuse with the radio. About 2years ago in the winter it wouldn't start. Of course i boosted it but the next moring it was dead again. I took it to my mechanic. He checked the alternator and replaced the battery (even through it was new). It started 3 days in a row but then went back to the previous behavior. I took it to another mechanic that said the same think as the 1st that it was the battery replaced the battery again (with much reluctance), this time it started for about 3 weeks. Both Mechanics agreed it wasn't the alternator. Once summer came the jeep started fine no boosting necessary. Last winter I just boosted it all winter and it ran fine, only lost the charge over night.
This winter it is still doing the same thing except it wont hold a charge at all and my CD player is making a funny clicking nose when I shut the jeep off. If I turn the ignition on the clicking nose meoves to the power window switch when you push it. I am thinking that there is a short somewhere but have no idea how to find it. Does anyone have any ideas?
 

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Welcome to the JK forums.

In the past, when I have had similar issues.... It was never fixed until I replaced the alternator, the voltage regulator and the battery.

But your issue may not be the same.

A dead battery is a result of a problem almost not "THE" problem.

I would agree that you probably have a parasitic drain that exceeds the norm as all vehicles have a drain.

Disconnect the positive side of the battery over night and see if that allows the vehicle to restart in the morning. Keep doing this and see if you last longer than 3 weeks.

Your alternator may not be recharging the battery but I would lean more towards a large parasitic drain. That will be a fun one to track down but almost always is the stuff you added aftermarket. A radio that is left on would certainly drain a battery overnight as an example.
 

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You need to find a mechanic that's certified in automotive electrical systems. It should only take about 15 to 30 minutes to tell you you have a parasitic drain and which circuit it is in. After that it could take anywhere from 15 minutes to a day tracking down the actual problem. Then you have to add the time and parts to fix it.

Decide how much you're willing to spend fixing it. It may be much cheaper (but a big hassle) to install a battery switch and turn it off each night.

Bottom line, get someone that knows what they're doing.
 

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Here's what I do.
Turn everything off and close the doors. If you have a radio with a digital clock, pull the radio fuse.
Disconnect the positive battery cable and put a volt meter beteen the post and the terminal. If you have a drain it will show on the volt meter.
Pull all the fuses. If you still shows a drain, the short is between the battery and the fuse box.
If the drain goes away (0 volts) start replacing the fuses one at a time until the drain comes back Voilla!! you've found it.Pull this fuse, verify that the drain goes away.
Pull that fuse and continue with the rest of the fuses to see if there are multiple shorts.
Once you know the circuit you can try and find the short.. I had a friend who found a short on a wire that was inside the frame rail, so it might take a while.
If after pulling the fuses, or not finding the short........ "Seek expert advice"
Good luck:beer:
 

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I do this for a living and finding a parasitic drain is harder then you think,maybe easyer on a 1996,but you need to connect a volt meter between neg cable and the neg battery post,and set the meter on milli amp setting,most cars and truck now of days will have about 24 to 28 milli amp draw.With the meter set like this you can pull fuses or disconnect modules 1 at a time tell you get to that low milli draw.
 

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SoCal thanks for the heads up. I never thought about using the current draw instead of voltage. Learned something new today.:bounce:
 

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I do this for a living and finding a parasitic drain is harder then you think,maybe easyer on a 1996,but you need to connect a volt meter between neg cable and the neg battery post,and set the meter on milli amp setting,most cars and truck now of days will have about 24 to 28 milli amp draw.With the meter set like this you can pull fuses or disconnect modules 1 at a time tell you get to that low milli draw.
Most multimeters can only measure up to 10 amps. If you run more than that through them, you can blow a fuse in the meter. It's easily replaced but you'll probably have to take a half hour to run to the hardware or Radio Shaft store to get one. If you have one laying around, use an old automotive ammeter first, hooked up like so_calif_rubi says, to make sure the total draw is less than 10 amps before you hook up your multimeter.

When checking these things out, I like to start with all the fuses pulled. If you have a current draw then, it could just be wet mud in the starter. If you have no current draw then, check 1 circuit at a time by installing it's respective fuse. Make sure you write down each reading you take and the circuit you're checking. Pull that fuse and put in the next one and take your reading and record the value. Repeat until done.

When you're all done with each circuit, put all the fuses in and take a reading. Write it down. Add up all the individual circuit loads and see if it matches the reading with all the fuses in place. It doesn't always.

Once you figure out which circuit is draining your battery, you can start disconnecting one device at a time on that circuit to see what's using that power. As before, take good notes.

One thing to remember, your dome lights will draw a lot of power (a few amps) so keep your door shut when taking readings.Another thing is dont try to start the vehicle with the meter hooked up.
 

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Yes alter is rigth i allways start with my 10amp setting on my meter.And yes never do any large loads like turn on Ign,start or open doors while checking for draw.I open doors befor testing and close the door latchs with my pocket screw driver,so the bcm thinks the door are closed.and then i see it under a 10 amp draw.then ill go to a milli amp setting.today at work we had a Trailblazer with a large draw,found that the OnStar module was the problem.found this by disconnecting 1 module that a time.
On older cars could be a wire rubbing on the body,Alt,and mud in the started like Alter said.
Ive seen alarms do large draws,Lojack is the biggest drawer of all.
 
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