The switch at the dome light is a simple on/off switch. If there was a problem at another point, the light would likely not turn off when you press the on off button.
Based on that theory, I suspect the switch at the dome light is bad and slowly is making a connection internally until you turn it off again.
If you look at the pics below, I attached the entire wiring schematic for these lights. Note the power to the dome light is shared with many other lights. Therefore, if the issue was before the dome light, the others would likely turn on as well.
I would replace the dome light assembly. Or, I would at least remove it from the overhead console and inspect the wiring.
Here are the directions for removal and replacement. Pic 3 below correlates with the directions.
1999 Chevy Truck C 1500 Suburban 2WD V8-5.7L VIN R
Dome Lamp Replacement
Vehicle Lighting and Horns Dome Lamp Service and Repair Procedures Repair Instructions Dome Lamp Replacement
DOME LAMP REPLACEMENT
See pic 3
CAUTION: Refer to Battery Disconnect Caution in Cautions and Notices.
1. Disconnect the negative battery cable(s).
2. Remove the lens.
3. Remove the bulb.
4. Remove the housing screws.
5. Remove the housing assembly.
6. Disconnect the electrical connector.
7. Remove the bezel.
1. Install the bezel.
2. Connect the electrical connector.
3. Install the housing assembly.
4. Install the housing screws.
5. Install the bulb.
6. Install the lens.
7. Connect the negative battery cable(s).
Let me know if this helps or if you have other questions.
Take care and God Bless,
Images (Click to enlarge)
Wednesday, May 26th, 2021 AT 11:42 AM