might have a short in the wiring to the light socket!! same happen to me...
Generally the light switch pod. Get on ebay and but a new one
Most likely the resistor has gone out! Check the fuses; undersize fuses will not work!
The switch is probably bad or you aren't turning the knob all the way off.
My '93 Sport does the same thing periodically. This may be a cool safety feature Jeep uses to indicate your brake lights are not working. If this is the case it is as simple as replacing fuse or bulbs. if your lights flicker on and off i wouldheck for a short in your electricle systm or if they went out and stayed out i would start by checking the fuses in your fuse box.hope this helps.
Check fuse for tail and parking lights Could be a bad dimming rheostat Could be a bad headlight switch
Got the same problem on a 1999 jeep Cherokee sport and the problem appears to be due to the fuses. They are located under the hood on the passenger side (it's a box that can be easily opened). In it you'll find the fuses for the fog lights(it is supposed to be written at the backside of the lid). Just don't forget to unplug your batterie before touching it, it could make your "check engine" to light. I did replace the two fuses(didn't take chances). Then it is supposed to work fine...
If you are referring to your guage lighting, is the dimmer switch thumbwheel to the right of your headlight switch turned all the way down ? I'm not sure about your O/D OFF & speed control lights.
in stall fog lamps it helps a lot or ultra whites from auto store
My '96 Cherokee Sport does, so I bet a '98 does.
Assuming you have replaced the bulbs with no joy and the fuses are good, your problem may be linked to the Neutral Start Switch on the side of the transmission. This switches on that circuit when the transmission in in reverse. Many times the contacts inside it become worn or dirty. It can be disassembled cleaned and re lubed or simply replaced. Hope this helps.
Turn on the radio and start pulling fuses. When the radio stops working, that is the fuse. Try the cigarette lighter fuse first.