Understanding the overhead console

Full disclosure, I'm a TJ guy but I'm also the "electrical expert" in my group (which is incredibly scary) so when the XJ has electrical trouble, it's up to me to solve it. What we've got is a 1999 XJ that's got a parasitic drain of about 130mA, which I've isolated to fuse 16 in the PDC.

I'm going through the wiring diagrams, but I'm thoroughly confused when I trace the M1 circuit as it goes to the "Overhead Console," particularly because it seems to tie into the door lock function & horn sense relay (page 8W-49-4 if you're playing along at home) and also because our "overhead console" has a light and nothing more.

So maybe the overhead console isn't what I think it is, or I'm looking at the wrong flavor of wiring diagram or who knows what, but I can't reconcile the locks (and horn?!) going through what I would call the overhead console.


Any guidance here would be appreciated.

If the XJ has power locks/windows/mirrors, it likely has key-less entry also. The key-less entry module is located in the dome lamp, or in the optional overhead console.

The keyless entry module has been known to fail, it is not common, but has happened a few times. Unplug the dome light wire harness from the fuse box and see if the parasitic drain stops.

There is zero evidence that this one ever had keyless entry, although it definitely had power windows/locks/mirrors. But no fancy stuff in the overhead console or the rearview mirror (if that was ever a thing, IDK).

hbar.. said:

Full disclosure, I'm a TJ guy but I'm also the "electrical expert" in my group (which is incredibly scary) so when the XJ has electrical trouble, it's up to me to solve it. What we've got is a 1999 XJ that's got a parasitic drain of about 130mA, which I've isolated to fuse 16 in the PDC.

Click to expand...

Have a look at page 8W-10-25. Fuse 16 feeds a bunch of stuff, including courtesy lights, the radio and tcm keep-alives. Glovebox or cargo light stuck on? The radio may pull some current when it initially turns on - saw that with mine as it tries to eject any CDs when it first gets keep-alive power.

lawsoncl said:

Have a look at page 8W-10-25. Fuse 16 feeds a bunch of stuff, including courtesy lights, the radio and tcm keep-alives. Glovebox or cargo light stuck on? The radio may pull some current when it initially turns on - saw that with mine as it tries to eject any CDs when it first gets keep-alive power.

Click to expand...

The visors & kick panel lights don't seem to be stuck on. No light in the glove box as far as I'm aware, and the under hood lamp I have unplugged. The cargo light I can't really speak to; I know I never saw it on, but for all I know the bulb is burned out or it's switched off. There is a stereo, but its never on since there are no speakers.

I've traced the M1 circuit and understand it (aside from the overhead console piece), and we had some reason to believe the parasitic draw was related to the windows....we've done a ton of "maintenance" on the windows, such as relocating the switches to the center console and essentially eliminating the door lock & mirror functions. But the windows still work w/o fuse 16, so that's probably not the source.

The overhead console confused me because (a) we don't really have one and (b) fuse 16 did seem to have some involvement with an area we seriously messed with. Having said that, the parasitic draw has only started in the last few weeks, and we did the windows months ago (and that wiring is super clean). I can't tell if the overhead console stuff was an option; usually the diagrams show optional stuff as optional, but no such indication in this case.

Thanks for your input, I'm all ears on how to track this one down.

All I can say is even if there is no console jeep generally included the wiring so maybe there is a pinched or pierced wire somewhere?

We'll definitely be checking out those areas.

What keeps brining me back to the windows is that this parasitic drain problem just suddenly started happening right around the same time one of the windows stopped working (one of the spade connectors on one of the console-relocated switches slid off [I used 4 DPDTs to control the windows]. I see they're not on the same circuit, but seems like coincidences like this are rarely coincidences. Also this all started immediately after the jeep was loaned to a friend to use the winch to pull out some bushes. So there's no telling what all happened while he had it.

We'll figure it out, eventually.

Haven't had a ton of time to troubleshoot this issue, but I did have him unplug the dome light during a period where we knew the jeep would be sitting for several days. Came back, no trouble starting.

Then last night I tried to check the current flow with the dome light plugged in/unplugged but apparently I'm too stupid to use my multimeter in ammeter mode, because it blew a fuse. It'll be a couple days before we can look at it again, so he's got the dome light plugged back in to see if it again has trouble starting.

hbar.. said:

..........There is a stereo, but its never on since there are no speakers..........

Click to expand...

If the stereo is still connected to power, it can cause a drain. It too
has a keep-alive memory for pre-settings. I'd unplug it just to take
it out of the loop.

(I replaced a stereo a while back for the exact same kind of power drain.)

I'm not sure if the 99 has systems that stay energized for a while after key off. how long did you monitor the current draw? but Radio will draw power along with the ECU

after many drains, and much time drained, a battery can be ruined.