Mysterious Battery Drain: Don't Drive It Enough?

Mambolicious

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I have a 2002 Wrangler Sport with 4.0 L 6 cylinder - Battery issues have been popping up for a few years. Some people have blamed airport parking: "parking your car at the airport drains the battery." Others blamed the alarm system and I removed the alarm. Mechanics have fixed everything else, like the starter, alternator, spark plugs, etc.

Yesterday, the mechanic told me that the battery, that they installed October '21, is dead because I don't drive the car enough. Is that a thing?
 
Sure it's a thing. But how much is not enough? If you only drive it once a week, or a month, and if you don't drive it for a half hour each time to charge the battery up, you could be draining it. You would have to neglect it a lot to kill an 8 month old battery.
 
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Thanks for your reply, OldBuzzard:)

It's more of a weekend vehicle to go to clubs at night. Maybe half hour there and back. Plus, in NYC, we have to move our vehicles once a week for street cleaning. So, I spend time looking for parking.

Sometimes, it does sit for a couple of weeks before I start it again. How much would I need to drive it to solve the problem? Are there any other options to keep the battery charged?
 
Just my .02

I have a 2000 sport. I noticed that I can remove my keys while in accessory position (all the way back). I have done this a few times only to come back to a dead battery. My jeep is a beach buggy so I don’t have alny interior lights or buzzers hooked up.

My solution. I added a usb cigarette lighter charger that lights up in accessory mode so that I can verify my key has been moved correctly. Haven’t had an issue since
 
Mine is not a daily driver. I have a trickle charger that I hang from the hood catch when it's going to be parked for more than a few days.
 
I have a 2002 Wrangler Sport with 4.0 L 6 cylinder - Battery issues have been popping up for a few years. Some people have blamed airport parking: "parking your car at the airport drains the battery." Others blamed the alarm system and I removed the alarm. Mechanics have fixed everything else, like the starter, alternator, spark plugs, etc.

Yesterday, the mechanic told me that the battery, that they installed October '21, is dead because I don't drive the car enough. Is that a thing?

Yes, it is a thing. First, all batteries exhibit a property called 'internal resistance', which means, left alone for long enough they will discharge. Second, today's auto batteries store a lot of power and have low internal resistance, which means you should be able to leave it sit for a couple of weeks with no problem. It sounds to me like you may have 'phantom drain', that is something in your Jeep is using battery power unknown to you.
To find out what is draining your battery, all you need is a cheap (HF, HD, or Lowes) multi-meter. Set the multi meter on Amps. Pull your fuses one at a time, inserting the probes from the meter into the fuse slots. You can get some small probe extensions to fit the slots, or just use paper clips. Eventually, you will get a reading of 500 milliamps (mA) or more. See what equipment is on that circuit and you have found your culprit.
It usually turns out to something added to the Jeep's electrical system along the way, such as a new radio, alarm system, or other accessory.
There may be more than one, so check all the fuses.
If it turns out to be something you want to leave on, that's fine. Just use one of the suggestions above to keep your battery charged when you are not running the engine.
Good luck!
 
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Yes, it is a thing. First, all batteries exhibit a property called 'internal resistance', which means, left alone for long enough they will discharge. Second, today's auto batteries store a lot of power and have low internal resistance, which means you should be able to leave it sit for a couple of weeks with no problem. It sounds to me like you may have 'phantom drain', that is something in your Jeep is using battery power unknown to you.
To find out what is draining your battery, all you need is a cheap (HF, HD, or Lowes) multi-meter. Set the multi meter on Amps. Pull your fuses one at a time, inserting the probes from the meter into the fuse slots. You can get some small probe extensions to fit the slots, or just use paper clips. Eventually, you will get a reading of 500 milliamps (mA) or more. See what equipment is on that circuit and you have found your culprit.
It usually turns out to something added to the Jeep's electrical system along the way, such as a new radio, alarm system, or other accessory.
There may be more than one, so check all the fuses.
If it turns out to be something you want to leave on, that's fine. Just use one of the suggestions above to keep your battery charged when you are not running the engine.
Good luck!

Thanks so much for your sharing your insight, Dr. Internet! I do have an after factory sound system and amp. Pulling fuses is beyond my purview so I might have to take it to a mechanic. Or maybe the dealer? It's crazy that no other mechanic has suggested that and it's been to at least 3 different mechanics. Would you happen to know if there's a place that I can take it for that type of testing?
 
Just my .02

I have a 2000 sport. I noticed that I can remove my keys while in accessory position (all the way back). I have done this a few times only to come back to a dead battery. My jeep is a beach buggy so I don’t have alny interior lights or buzzers hooked up.

My solution. I added a usb cigarette lighter charger that lights up in accessory mode so that I can verify my key has been moved correctly. Haven’t had an issue since

Thanks for your reply, Dpet88:) I actually have internal lights and I to push a button to pull the key out. So, that's probably not the issue but I will be more mindful of that.
 
Are you certain your aftermarket amplifier is actually shutting off when you park your TJ? Some car audio installers are barely more competent than a trained monkey and may not have wired it correctly to shut off automatically either from shutting the radio/head unit off or the ignition switch. Does it have a light indicating if it's on or off?

Also, some alarms use a relay and if they wired up the relay backwards so it remains on unless the security system is activated that would drain your battery too. Make sure all of the old alarm system is gone including any hidden relays the installer might have placed in an out of sight area.
 
Are you certain your aftermarket amplifier is actually shutting off when you park your TJ? Some car audio installers are barely more competent than a trained monkey and may not have wired it correctly to shut off automatically either from shutting the radio/head unit off or the ignition switch. Does it have a light indicating if it's on or off?

Also, some alarms use a relay and if they wired up the relay backwards so it remains on unless the security system is activated that would drain your battery too. Make sure all of the old alarm system is gone including any hidden relays the installer might have placed in an out of sight area.

Hi Jerry, thanks for your response. No I'm not sure if it's shutting off. The amp is underneath the console. There used to be a blue light but I don't see it anymore. I'll also have someone look into the hidden relays. The alarm had a kill switch. Initially, They told me they were going to charge me about $80 to remove the alarm but for some reason they waived the charge. Of course I was wondering why.

I just called one mechanic and they have no interest in testing anything. This is the worst part of having a TJ in NYC —-finding a good mechanic.
 
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Interesting on the battery drain. I'd say you have a phantom drain somewhere. When I bought my 2000 TJ from my parents in 2015, my dad said I should probably replace the battery soon. It had been 7 years since a new one and what he replaced was the factory battery. I bought a new battery in 2015 and my TJ will sit months at a time in the winter without a problem. Just jinxed myself didn't I?

I would do like Dr Internet says and get a multi meter and start checking for current pulls.
 
IMO, you should be able to park it for weeks and still start it.
However, if you don't run it enough to recharge what you used to start it, it will slowly die.
Especially if those short drives include using your headlights, stereo, etc.
 
Interesting on the battery drain. I'd say you have a phantom drain somewhere. When I bought my 2000 TJ from my parents in 2015, my dad said I should probably replace the battery soon. It had been 7 years since a new one and what he replaced was the factory battery. I bought a new battery in 2015 and my TJ will sit months at a time in the winter without a problem. Just jinxed myself didn't I?

I would do like Dr Internet says and get a multi meter and start checking for current pulls.

Ok, thanks for your reply & suggestion, Fantix:) With all of these helpful replies, I am so happy that I joined this forum.
 
IMO, you should be able to park it for weeks and still start it.
However, if you don't run it enough to recharge what you used to start it, it will slowly die.
Especially if those short drives include using your headlights, stereo, etc.

Thank you for your reply, LONGJP2. Yes to short rides, in traffic, with headlights and stereo. I think I found a place for testing for the phantom drain and adding a trickle charger.
 
Both my 89 YJ and 05 TJ sit fir long periods and I had the same issue. I just installed battery cut of switches and have not had a dead battery since. I know it clears the PCM but that has not been an issue.