Parasitic battery drain

Let it sit there for awhile and keep your eye on it. See if the draw stays at 100ma or goes down further.

I wish I knew what was considered acceptable on a TJ.
 
primetime4 said:
Are you sure there is a 20 amp setting? I am assuming 10 amp in which case 100 milliamps is correct. I think that is too high going by the 50 milliamp threshold. I remember testing my Jeep and it was actually much lower than that as you can imagine. I would start pulling some fuses to see how close to zero you can get it. Alternatively, you can also just disconnect whatever you think the offending component is and see if that helps.
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Went back out to investigate further. Here is a pic of the meter reading when set on 20 amps. When I initially touch the leads to the negative battery terminal and the ground wire for the battery, I get an initial reading of .30 which then settles down to .06 in a second or two. I was able to get the reading to 0.00 by pulling the # 26 - 10 amp fuse for Accessories. The only accessories that have been installed are a winch, which is currently disconnected pending the installation of a power interrupt solenoid and switch, and an aftermarket radio unit, but that has been installed for over a year and I don't recall using any power wire other than the stock radio. I will pull the radio fuse to see if the radio is connected to it.

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I would try and find what is powered by that fuse, as it looks like 100% of the 60 milliamp draw goes through it.

I would get some gator clips on the ends of your leads and leave the meter hooked up for awhile. switch the meter to 200ma setting and look for a more precise reading over time.

Make sure it stays on the 20a setting when initially hooking it up like you have.
 
That fuse is the Accessories fuse, after pulling it just now and inspecting the Jeep when running, the radio still works, the fan still works, the headlights and taillights all work. The only things on that 10 amp fuse that didn't work are the two dome lights on the speaker bar and the courtesy lights on the passenger and drivers foot well. All lights go off when the doors shut or when I depress the door switch while checking. Here is what I'm finding in the Service Manual for Fuse # 26

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I feel like I've read that the underhood light has killed people's batteries before, maybe somebody can chime in? I've never personally experienced it.

Either way, you can unplug each of those components one by one to find out if they are somehow causing a draw. I'm assuming you're doing your draw test with all the doors closed.
 
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Rubicon John said:
I feel like I've read that the underhood light has killed people's batteries before, maybe somebody can chime in? I've never personally experienced it.

Either way, you can unplug each of those components one by one to find out if they are somehow causing a draw. I'm assuming you're doing your draw test with all the doors closed.
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That's actually funny because I disconnected the under hood light last year when I did all my engine work and never reconnected it. The testing you mentioned is my next step, although disconnecting the instrument cluster will be final item on my test list. And yes, doors are closed for the test.
 
Rubicon John said:
I feel like I've read that the underhood light has killed people's batteries before, maybe somebody can chime in? I've never personally experienced it.

Either way, you can unplug each of those components one by one to find out if they are somehow causing a draw. I'm assuming you're doing your draw test with all the doors closed.
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I have heard of the same problem with the under hood light not shutting off due to a stuck internal switch or the light is loose on the hood.
 
I may be losing my mind. Tonight after dinner I went out the to TJ, disconnected the ground cable from the battery and connected my amp meter to both the battery terminal and the cable using alligator clips. Previously, I had just be touching the leads to the cable and the battery.

Previously, I had determined that when i pulled fuse # 26 for accessories (interior lights) that I could get the parasitic drain to go to zero. Before I turned on my meter, but after disconnecting the battery, I got in the Jeep and pulled the dome light bulbs (2 of them) out, shut the door and turned on my meter.

When I connected the first alligator clip to the meter lead, on the 20 amp setting, I got an initial reading of 0.3 and as I was watching it, it went to zero in about two seconds. Thinking it was a mistake or lose connection, I rechecked the alligator clips and cycled the meter on and off. When I reconnected the lead to the meter, the exact same thing happened, after two seconds the reading went to zero.

I then got in the Jeep and inserted one of the two dome lights, since the meter was on the 20 amp setting, I left it connected. When I inserted the one dome bulb the reading was 2.4 amps. As I closed the door and the lights slowly dimmed the reading went to zero. So I inserted the second dome bulb, after it was inserted the amp reading was something like 3.5 amps, but as I shut the door and the lights dimmed, the reading went to zero.

Now I am not complaining that I have no parasitic drain, but scratching my head at my earlier results and my battery issues. Now that it is fully charged I am going to drive it for a while every day for a week and see if I have a repeat of the dead battery issue.
 
I am attempting to do this but it appears my DMM does not have the right scale on the amps side. Am I reading this correctly?

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Flivver250 said:
Have you load tested your battery?
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My earlier post indirectly asked the same question and I do not believe the question was answered.
In the first post he said he had taken the battery to AutoZone and O'Reilly's and they said it was good, but with the battery not being fully charged there really isn't a way to make an accurate test.
I suspect what they did was just put a multi-meter to the terminals and made the judgement by the voltage without a load... I wonder what voltage was considered good in their book.

Years ago I had an Optima Red top battery that was BAD in my book, but when tested at 4WP I was told the battery was good. I asked them what voltage was good to them; they tech said 11.5V.
I had previously contacted Optima Customer Service and talked to their Tech; the Optima Tech said anything less than 12.3V after a load test (allowing 1-2 minutes to recover) was considered a bad battery and needed to be replaced.
When I provided the 4WP representative the Optima Customer Service techs name and number; he called the Manager and the Manager said...., Just give him a new battery....
 
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My daughter’s car had the same problem. Oreily’s and Auto Zone both tested the battery as good. I couldn’t find anything else and replaced the battery and it’s been fine since then. The battery can be the drain, a shorted cell will drain it over time.
 
I now have a fully charged battery by letting the tender stay on it over 24 hours. The Jeep has now started two days in a row with no difficult. The dash gauge is reading 14 volt charge, but I am still suspicious of the battery, despite having a date of June 2018 on it. I will continue to monitor and replace if this happens all over again.

This weekend I installed a set of battery tender charging leads to the battery terminals and routed the wiring to the front fender area. The plan is to pull up next to the garage and attach the tender to it much easier than opening the hood and installing the alligtor charging clip to it each time.
 
BobK said:
I now have a fully charged battery by letting the tender stay on it over 24 hours. The Jeep has now started two days in a row with no difficult. The dash gauge is reading 14 volt charge, but I am still suspicious of the battery, despite having a date of June 2018 on it. I will continue to monitor and replace if this happens all over again.

This weekend I installed a set of battery tender charging leads to the battery terminals and routed the wiring to the front fender area. The plan is to pull up next to the garage and attach the tender to it much easier than opening the hood and installing the alligtor charging clip to it each time.
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Sounds like you have the problem handled... (y)
 
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I ran a wiring harness from my battery along the same route my winch cables go. It has the Battery Tender plug on it sticking out the grill. I can hook up the battery tender there to charge the battery. I also modified my portable compressor cable to use the same plug. I can charge battery or air up without opening the hood.
 
primetime4 said:
This is the video I referenced when searching for a parasitic drain in my Land Cruiser and he does a great job explaining.

Ultimately, it turned out to be the CD player. There was a disc stuck in the magazine and the player just kept spinning. I would check if you have an aftermarket alarm system or head unit especially if it has Bluetooth.
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Bluetooth you say? Why so?
 
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