Parasitic Battery Drain...

PaulJensen

Custom Builder
Why would there be any power going to the rear tail/brake lights with the key out...???...

Early this morning I noticed a very faint glow from the LED tail lights...

A single "bulb" on the passenger side and nearly all the "bulbs" glowing very faintly on the driver side...

I installed a knife-blade battery cut-off switch (neg. side) in the engine compartment, so that kind of solves it, but not really...

I am looking for the long term fix...

Thanks in advance...
 

Herbie

Rendezvous Conspirator
Can't say for sure, but I do know that on my Chevy, a lot of the lighting circuits are switched ground, so there's a constant hot and the grounding leg either floats or is tied to ground.

If a similar arrangement used on the Jeep, then possibly there's a short or sneak circuit somewhere that's bypassing the normal switch mechanism and providing a partial path to ground. The fact that it's a faint glow suggests some resistance in the path somewhere...
 

Teamoatmealpie

Observer
Had a similar experience with my jeep. The open door/key in ignition buzzer would go off all by itself with no keys in it. Sometimes the head lights would come on all by itself with no keys in it. I had dealer look at it several times, they never sorted it out. Got to where I would disco the battery when I parked it = pain in the ass. I hope you are able to sort this out, electrical stuff is never fun.
 

mog

Kodiak Buckaroo
Why would there be any power going to the rear tail/brake lights with the key out...???...
Early this morning I noticed a very faint glow from the LED tail lights...
Perhaps 'zombie' LEDs (not a joke, real deal, see video)
Basically the LEDs draw so little power that the wiring acts as a capacitor.
Above my pay-grade, so the video explains it better.
 

Vinman

Observer
I would start by carefully inspecting all the bulbs, I seen a dual filament bulb break one filament which happened to fall against the other filament and back-fed the other circuit, that was a bugger to figure out.
Another was like already posted above, switched ground instead of positive. My dome light would not turn off once in a while and the fix was simply a new bulb, that was on a mid 70’s GM car.
If you happen to have a light that is switched ground and one filament shorted out against the other, it would provide power to that entire circuit.
 

FlipperFla

Active member
Why would there be any power going to the rear tail/brake lights with the key out...???...

Early this morning I noticed a very faint glow from the LED tail lights...

A single "bulb" on the passenger side and nearly all the "bulbs" glowing very faintly on the driver side...

I installed a knife-blade battery cut-off switch (neg. side) in the engine compartment, so that kind of solves it, but not really...

I am looking for the long term fix...

Thanks in advance...
Brake lights are on a always on circuit, not ignition. I would be looking at the switch at the brake pedal not completely disengaging. Put a voltmeter on the output of the pedal switch and see what you have.
 
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NatersXJ6

Explorer
JK models are known for all sorts of random electric failures in the Integrated Power Module, google IPM failure and you’ll see it. I would start cheaper and look at the brake switch first though. I believe you should be able to see the brake switch signal on the bus with a fairly basic diagnostic software package.
 

shays4me

Willing Wanderer
I would start by putting an oem tail light back in it. Often times aftermarket parts are way less reliable than oem (most of the time) and your wiring is not designed for low draw leds. That would be the easiest fix. If the standard bulbs are on and running your battery down, check the brake light switch, it probably needs adjusted.
 

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