An isolation switch
There may be an issue with the relay switch going to the radio lights. There may also be an issue with the fuse.
try replacing the dimmer switch they sometimes go bad and do not allow voltage to the lights
bad wireing or your insterment panel dimmer switch is bad
The switch is below the radio.
broken circit in your light switch
I believe the push button switch for the factory fog lights is in the center stack of your dash , just to the right of the radio , near the bottom of the radio
The dash lights and lights to the gear shift panel are grounded through the radio, be sure that the radio plug and ground to radio are connected. If you have taken out the radio you may try grounding the plug wire that connects to the radio lights.
pull headlight switch OUT toward you and make sure the fog light switch is pressed. It is located on the dash near the radio if they are factory lights.
The fog light switch is in the center stack of your dash , just to the right of the radio , near the bottom of the radio . Just push the button to turn on the fog lights and push it again to turn off the fog lights
The instrument cluster lights have their own fuse. It's a 5 amp at the bottom center of the fuse block. When the lights are on, the radio draws lamp power from the instrument cluster. This allows you to dim the brightness of the radio display with the other internal lamps.
If the dashboard dimmer switch works with the other dash lights, the fault is in the radio unit itself.
bad wireing or your insterment panel dimmer switch is bad. the switch is a dealer only part so get one from a junk yard or new its up to you