How do I change a brake light bulb on a 2002 silvarado?

There are two screws on the side that are accessed by lowering the tailgate. The outer edge of the tail light assembly is held in with clips. Pull it out to access the bulbs from the back. Hope this helps
How do I change a brake light bulb on a 2002 silvarado?
the assembly that the wire conn hooks to is like a circuit board

Test the wire that supplies power to the assembly

should be brown/left side brown%26amp;white/right side

If you have power on the wires and have good bulbs then the plate that holds the lamps and the wire harness plugs into needs replced

it can be purchased at NAPA parts stores

also there are 2 fuses for stop lamps both under hood fuse block 20 amp/10 amp the 20 amp fuse is the one for rear stop lamps