Chevrolet Repair: brake lights, turn signal switch, chevy truck

Question
I have a 94 chevy truck that the brake lights don't come on. I've already replaced the swith under the steering colunm, but only the light on top comes on. what could be wrong

Answer
Hello Alex,
The bulbs could be burned out.
If it uses the same bulbs for stop and turn, try the emergency flashers to see if the bulbs are good.
The signal flasher might possibly cause one to not work, but I doubt it would keep both from working.
Then there is the turn signal switch, and related wires and connectors, as well as the signal fuse. The stop lights go through the turn signal switch, except for the high stop light, which operates from the switch you replaced.
So check the fuses, then wiggle the signal connectors, firewall bulkhead connectors, etc.

Van