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Discussion Starter #1
Hey guys!

I have an 09 JKU that I keep having to jumpstart every couple days of not driving it. I can tell its a slower drain because if I try to unlock it, etc after about a day I can tell its struggling with less power.

I have gotten the battery, alternator, etc. tested and they are all solid. And no, I do not have any lights or anything else left on when I'm not in it. In fact I even have it set where the lights don't turn on with the doors open. I have added nothing electrical.

I have no clue what is causing my battery to go dead so frequently and quickly. Has anyone had similar issues?

I appreciate any advice or suggestions anyone may have. Thank you!
 

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If nothing is on you have a bad battery, put a multimeter on it while it's running to check the alternator but seriously doubt it if once it runs its fine.
 

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Batteries deteriorate. OEM batteries these days rarely last the 3 years that used to be the standard. That said, how old is your battery? You said it checks out fine. Who checked it? Was it load tested?
 

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My OEM battery lasted 3.5 years. It never gave any indication that it was dying, but I didn't drive it for a week and it was so dead I couldn't unlock the door with the Fob. My two OEM Ford SuperDuty batteries lasted 7-8 years.
 

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I too have my doubts your battery is fine. When you drain a battery down low like that a few times it is done. It will never hold a charge again. Modern vehicles are power hungry and it you don't have a proper functioning battery they will drain them fast. If you don't drive the Jeep much I would also get a battery tender to keep the battery charged up while it is sitting.
 

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I too have my doubts your battery is fine. When you drain a battery down low like that a few times it is done. It will never hold a charge again. Modern vehicles are power hungry and it you don't have a proper functioning battery they will drain them fast. If you don't drive the Jeep much I would also get a battery tender to keep the battery charged up while it is sitting.
If you are referring to me, I got a new battery that day.
 

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Discussion Starter #7
drain help

Thanks for the replies!

I will respond to questions etc. in order. I very much appreciate it!

My battery is about two years old. It is an interstate battery so I took it to the local store to have it tested and to have the alternator tested. They told me that everything is working and charging well, and the voltage it charges to is not indicative of a bad battery. That being said, I am beginning to get the feeling that the staff members I worked with have limited skills in the matter and don't know much outside of the basic testing process. I asked if they could test whether there is some drain occurring on the battery and they said no, but my research shows that it is actually pretty simple to do so. I will buy a multimeter and work on that.

My Jeep has been doing something similar to what azyjjk experienced. I was driving it more regularly but still occasionally the power would be low enough my fob wouldn't unlock the doors or it would struggle to unlock. It would recharge once driving. Now the battery drain occurs much more rapidly and its dead within 2 days of not driving. (And real low after 1 day)

I can take it back in to interstate and possibly just get a new battery. Despite their tests it may just not be able to hold a charge. If the same thing occurs I guess I'd know there is a drain caused by something else. Although I wouldn't want to ruin another battery.

I will look into a battery tender. I drive it as much as I can but I use another vehicle for work everyday so its not as often as I like. But if it keeps this sort of thing from happening in the future it is worth it. This is so annoying.

I really appreciate all of the help guys. If I can figure this out it will save me the $100/hr the mechanic will charge to look for the problem. Could get expensive very quickly.
 

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You could disconnect the battery for the battery for the few days it sets. Reconnect and see if the battery is still able to crank the Jeep.
 

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Disconnect one of your battery terminals and put a meter on amp setting (10 amps should do, if nothing showing then switch to 1 amp range) between the post and the disconnected terminal and check the amp draw, I'm not sure of the Jeeps specs but I'd leave it for 30 minutes or so before checking as it takes a while for some of the modules to go into "sleep mode"

Again I'm not sure on the Jeep but the last vehicle I had do this on was a Suburban and the parasitic draw was supposed to be under 1 amp If it's showing a large draw of (I'm just guessing here) 1 amp or more then you have something drawing power, start by pulling fuses and watching your meter, if you see it drop significantly then you have found the circuit that the draw is on and you should be able to narrow it down from there.

Once you have found that circuit then start checking the wiring for any breaks, you can get testers (various types) that you can connect to the circuit then run the tester along those wires and it will indicate when the problem is found.

Just looking around online and the newer LX's (Charger, 300's, Challengers) have a 10-35 mA draw listed so I would imagine our Jeeps to be similar.

One other question, do you have anything plugged into the OBD port all the time ? I had a bluetooth adapter that I could hook up to my phone with various gauges on it and it would kill my battery after 2 days or so.
 

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I used to work month on month off in Australia and my jeep sat for 32 days without starting every other month for 2 years. I never had to jump it nor did it show any signs of a diminished battery.
 

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If you are referring to me, I got a new battery that day.
I was talking to the OP.

I am not sure how they tested it but to test it properly it should be charged to full and then load tested as nwbronco mentioned. Really though if it has been killed more than once it is probably toast. I killed a battery in my truck in two years because I didn't drive it enough (at the time) and ran the battery down too low twice. Batteries last longer when they remain at the high end of fully charged and while you may be able to leave your Jeep sitting for 32 days and have it start that is not what they are designed to do and I would not recommend it without a battery tender.
 
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