DangerRanger104

Goin nuts trying to fix this and idk what else to do. I've seen posts with similar problems but none can seem to answer the question. I have a 99 Cherokee 4.0
All of a sudden the running lights won't turn on. When I use the switch it doesn't work for the running lights, fog lights, and instrument pannel. But when I pull it all the way out ONLY the headlights go on. Problem because driving a blacked out jeep at night doesn't work. The tail lights will still work but ONLY when I apply the break. Checked every fuse and I know all the running and instrument pannel lights still work because when I use the auto start they turn on automatically no problem. But as soon as I turn the key in the car they go off. Sounded like a faulty switch so I swapped that out and same problem. I'd appreciate any help people can give. Thanks
-Brian

89EugeneXJ

Are there fusible links (I'm not sure if the newer models do)? If so, one of these could be the culprit. I had the headlights and radio go out in my 89 and it turned out to be one of the fusible links that fried.

DangerRanger104

But if it were the fusable links, then the lights wouldn't turn on when the auto start kicks in, right?
But also I'm getting the airbag light turning, the tachometer dying, and "no bus" showing on the odometer. I wonder if its all related but the other stuff has been happening since I had it. The lights are a new problem.

89EugeneXJ

I haven't messed with the newer cherokees much...

If it were me, I'd start at checking the fusible links (it's as simple as finding them, then gently pulling on them. If they pull apart easily, then you have a bad link). I'd also check ANY ground wires, such as at the engine block and manifold, as well as at the battery. Make sure they are clean and free of any corrosion or dirt/oil/grime. I'd also double check the fuses.

These are quick and simple things to check (15 min if you know where everything is) that are usually the problem-causers. If all of these check out, then I would guess that it's a short in the harness somewhere, which would be a PITA to figure out.

Hope this helps!

DangerRanger104

Thanks man ill try!

89EugeneXJ

No problem! Keep us posted on what you find!

CCKen

Check the fuses in the junction block, in the passenger footwell. If you have a '99 Chrokee Owner's Manual, page 186 & 187 shows the fuses in the JB. #23 is the right parking (running) lights and #7 is the left parking lights. Why two fuses would blow, I don't know. If they aren't blown, the lheadlamp switch might be defective.

DangerRanger104

Checked and rechecked both fuses. Both are good and I just replaced the headlamp switch and still having the same problem

CCKen

I'd have to dig through the diagrams to see what could be wrong.

Are you saying the runnng lights work when you do the auto start but not with the key turned to RUN, or any other key position? I don't have diagrams that would show auto start circuits.

The Rooster

I do not know much about 99's but a friend of mine had a similar problem and it turned out to be the ignition switch on his 98.. Does all the lights run through this ken? Like the older ones?

Reverend Blamo

Remove the driver side tail lamp housing, find the ground wire going to the housing (it goes to all the lamps) make a jumper wire and bring that to a good, KNOWN ground. If the lights work now, you have found the issue. Find the bad ground or make a new one.

DangerRanger104

I'll give it a shot. But if its a bad ground wouldn't they not work with the auto start too?

Cbagg

when remote starters are installed correctly, they tap into the existing wires with out cutting them. the factory wire could have been cut in this case, and is now not connected. so the auto start is lighting them up as IT is still connected but once the auto start is stopped, they go off. try checking where the auto start wires are spliced in.

good luck....

CCKen

Not to my knowledge. The lights are run off the battery bus. The association with headlamp switch is the ignition switch key-in switch.

DangerRanger104

Are the running lights tied into the no bus problem?