There could be a separate fuse for the lower brake lights , or maybe both
lower brake light bulbs are burned out
depending on the vehicle - some have a separate fuse for the third brake light
Check the switch. It has a different one than the regular brake lights. the light bulb could possibly be blown
I have the same problem - but my third brake light slightly flashes when the car is of (Explorer 1998). I have replaced the "stop light" switch with no improvement at all.
New bulb needed or broken wire
There are a couple of reasons a 1999 Chevy Silverado third brake light will not work. The first may be that the light bulb is burnt out. If replacing the bulb does not work, there may be loose wires to the connection causing it to not work.
Above the brake pedal. If your main brake lights dont work but your third center brake light does, then the brake light switch is not the problem. Its is the turn signal switch.
Your hazard/turn/cruise module in the steering column has failed. The third light still works because the third brake light switch is mechanical tied to the pedal.
This is most likely
The 2001 Chevy Blazer brake lights may not work and the third bake stays on because the current light needs to be replaced. A replacement brake light can be purchased at an Auto Parts store like Pep Boys.
first check brake light fuse second check light bulbs,they should be double element third check the brake light switch located on the brake pedal
this tells you is a simple wiring problem.most likely a loose wire from the third light to the other lights.(third lights provides the power to the other lights)
I believe that any light that is on your car has to work by law.