The engineer in me wants to see a graph of current draw overnight.


If you were in Hawaii, I'd think the Menehune were stealing electrons.

 

I did disconnect the alternator and had that tested. It passed two separate tests at two different facilities.

I have an aftermarket radio but that's it and it's been in the jeep since I bought it 5 years ago and I haven't had one problem with it. Regardless I pulled the fuse for it and I'm gonna leave the battery attached overnight just to see what happens. I also pulled the dome light just in case my car is haunted and that's coming on at night.

I'll get you a pic of the battery and terminals, sorry that hasn't come yet. I've been busy with my job lately and haven't had a chance to do much outside of work and sleep. I checked for places the terminals could be touching and I didn't see anything besides the hose that lays over the battery which has been there and seems like a standard thing in these jeeps.

Again, not a troll. If its gonna take me leaving references of the auto parts stores I visited then I will do that. Short of that you'll just have to take my word for it and belive me that I'm having this issue with my jeep and I'm just as confused as you all are. It legitimately starting to seem like an episode of House except with car guys and less witty banter.

 

What, the Menehune crack wasn't witty enough for you?????

 

Still don't see a pic of your + battery post/clamp!

Is your only indication of a problem in the morn is that the engine won't turn over?
If so, lets rule out some spooky starter/relay malfunction, maybe the battery drain isn't the problem.

When you pull the radio fuse out for the overnight test then:
Engine off for all these tests.
Turn on the headlights momentarily before going to sleep. Just to make sure the battery is up to snuff.
Then in the morn, engine still off:
-measure the battery voltage
-turn on the head lights, engine off. Do the headlights turn on? Dim? Normal bright?

If the headlights do not turn on, then its got to be something either draining the battery overnight or some odd issue with the battery draining over time with a mere 17ma causing it to go into some weird self-discharge mode.

Did you swap out the battery with a known good one?

If the battery is indeed dead in the morn, did you disconnect the remote lock/unlock printed circuit board located inside the dome light housing like i mentioned earlier?

 

Note from DJ
This is a long shot but if you have a power radio antenna it worth the time to check.

My 88 had the same problem as you; dead battery after parking overnight but no obvious problem.

Then one day I was standing with the hood up looking at the battery area before disconnecting the battery for the night.

All of a sudden I heard a faint humming sound that was coming and going from the fender back by the door.

It would hum for a very short period then be quite for a while.

It turns out my antenna was going up and down as it was designed to do but when it reached the down position it was not shunting off as designed to do; instead it was trying to continue to run in the down direction until the thermal overload safety in the motor would trip. Then when the overload switch cooled it try to run in in the down position again. The end result was an on and off attempt of the motor to run and a dead battery.

Fix was no more power antenna.

 

At this point anything is worth a shot! LOL!
By the way didn't know the old XJs ever had power antennas.

 

Pics of batt terminals.


I've cleaned the terminals multiple times since this started along with the posts.

Lights looked fine with the overnight test and everything started up fine this morning after pulling the radio fuse and the light. I'm gonna let it sit till tomorrow afternoon now and see what happens.

Dont have a remote entry on this vehicle. Also dont have a power antenna but thanks for the suggestions.

 

I can tell you, those cable ends look like ****. Could be half the problem. Intermittent connection.

 

Yeah they don't look picture perfect fresh right out of the showroom floor.
But i doubt thats the problem. Never can tell!

Just asking, is your place haunted? Ghosts around?
If no perceived spooks around, then either:
Your meter is lying
The battery is acting weird
Something in the Jeep likes to draw current when you aren't looking

Again,
is the only problem you can't start in the morning?
Have you considered the starter is the culprit?
Please respond to this.

Did you clean the innards of the clamp and the battery posts with one of these?

 

Cannot confirm that my place isn't haunted. Got new terminals just in case that was the issue and I'm gonna give the posts a thorough cleaning as well. As of now it seems like it might be the either the radio or light drawing at some point as it's been starting up just fine now with those powered off.

 

Play around with all the door switches to see if you can get the dome light too act up.
One of them might have;
an intermittent problem,
is on the verge of not turning off the light when the door is closed, corroded,
or defective.

Why this always happens in the middle of the night... maybe night time temperature fluctuation or more than likely one of those pesky electrical gremlin ghosts. lol

If its the radio, you're on your own.

Great you got a handle on it!
Does this mean we can we finally close this thread!

 

Yeah, that's probably not the source of the battery drain.


But starting problems? Oh, yeah.

 

Yeah re-looking at the pic, those clamps are squeezed to their limit.
I'll bet one or both of those clamps can even be turned by hand?
And to top that off maybe there's clamp/post contact corrosion.
Too bad the OPer didn't post that pic much earlier like asked to.

What gets me is the OPer indicated by disconnecting the battery at night and re-connecting in the morning it always started.
Could be reconnecting the clamp, out of dumb luck applied just enough pressure to start or night time drops in temp loosened the clamps a little more.

And now throw the disconnected dome light and after market radio in the mix and who knows.

To the OPer,
get those battery clamps changed and clean them and the posts with the tool i showed and take it from there.
Those battery post/clamp cleaning tools work well and are cheap insurance.

 

That's what I thought man, good to have someone in my court.

 

Yeah those clamps need to be scrapped.
If after all this spooky parasitic draw BS, if it turns out to be the clamps i'm gonna pop open a cold one.