Q: Dimmer light not working - 1991 GMC K2500

My dimmer light wasn't working in my 5 speed truck, and the instrument panel lights quit working along with the warning buzzer for turned on lights when you open the door. I am not positive about the buzzer being in this truck, but I’m sure about the panel lights going out. So I took off the dimmer switch to test the wiring. There were 4 wires and the only continual hot lead was the white wire. When I turned on the lights I only had the one white hot lead. When I turned the dimmer knob all the way up, my lower cab lights under the dashboard worked normally. My lights worked well - both the low and high beams. Should there be more than 1 hot lead on the dimmer switch when the lights are off? Should one of the other wires be a hot lead when the lights are on? Do you know what should be hot and what shouldn’t be hot on the wires to the dimmer switch? Are there relays I should be checking? It looks like there is a relay panel above the emergency brake foot pedal with 3 relay box devices.