Dome light trouble...HELP!!!!

Ok, so Im having a slight electrical problem. Everything in my jeep works, and works well...except for the dome lights. When i bought the car last week, it didnt have a bulb in the front or rear dome light, so i went and picked some up and when i put them in, the lights instantly came on. I thought this was odd since the door was closed, so then i thought i must have had the switch on. Nope. So thats my problem....the dome lights are on, and stuck that way. Cant turn them off with the switch or anything, and it doesnt matter if the doors are open or closed. Has anyone else ever had this problem?? Its not that big of a deal, but i would just like them to work for the sake of having everything working. Oh...its a 1991 Cherokee Laredo, 4.0, auto, 4WD. And other than that, no more electrical oddities....so what are your thoughts???

try twisting the head light knob?

Thats the switch i was referring to...it doesnt do anything. Tried it both ways and everything. Could it be possible that the switch is bad and stuck on? Ive had them go bad, but they always get stuck off and you cant make them turn on...

Could be that or a door pin/hatch pin is messed up

Yeah...thats what i was thinkin, i was just hoping that someone had had the same problem so that i could skip as much of the diagnosing as possible. Lol. Ill try to test them all tomro.

The door pins are normally open with the door closed. The switch is closed with the door open. The pins on the earlier models came with a little rubber cap on the switch pin, if it falls off the door pin/switch can be always on.
Simple test is to push the pins in one by one with your finger (all the way) and see if the lights go out.
If this fails the hatch switch is likely the problem, they turn into a glob of rust.
Some trim packages came with a rear cargo light; with a manual switch. On some models this switch will turn on all the inside lighting. The push button gets full of whatever and gets sticky.
If all else fails, you may have a ground short in the wiring under the drivers side carpet. There is a splice under there that Turns to a green glob of corrosion and can ground to the chassis. It's actually not a bad idea to look under there anyway, see if there is any rust you can catch and treat before it turns to holes in the floorboards (same on the passengers side).

Do you have courtesy lights or any other interior lighting, and is it behaving the same?

Interior cabin lighting is switched ground. There is one constant power, and then two or more possible ground points that can close the circuit. One ground is usually on the switch at the light which simply allows you to turn on the dome light locally, and the other ground is uisually sourced by the interior lighting circuit. The latter will typically feed the dome and courtesy lights, and will pickup ground from the door jambs and the headlight switch.

If the courtesy lights are not coming on -- but they do normally come on whenever a door is opened -- then you probably have an open ground at the light itself, such as a stuck button or the backing plate is touching the body.

open one door at a time, press the little button in the body that turns the lights off. check each door this way.

is the rear dome lamp switch switched on?

i dont think so...im pretty sure i tried it both ways, but ill do some more tests when i get home and let you know wat i find.

Ok...i just got home and messed around with it. It turns out that the switch in the rear passenger door is bad. So i took it out and im gonna go get one from Pull-A-Part tomorrow. But for now, the lights or when i open all doors but that one. :clap: