I have a 2000 Monte Carlo I put 2006 Monte Carlo tail lights on it all the lights works turn signal,hazard work ,tail guys all work l except the brakes when I push the pedal down it doesnt do anything no brake light ,

 

When you swapped the tail lights, did you used the light harness from your original tail lights or the 2006 tail lights?

 

i use the 2006 tail light harness ,when I try brake pedal it didn't light up so i installed my old harness from my 2000 Monte Carlo try brake pedal doesn't light up.both harness make the tail lights lit up,turn signal and hazard lights work

 

That is strange. I would validate all the bulbs are good (some bulbs have two filaments, one filament is just the tail lights and the other is used for braking or turn signal use). Otherwise, you will need to get a volt meter and wiring diagrams and start chasing it out. I assume it all worked before swapping the tail lights..... May also want to double check the fuses (not sure if there is one that affects brake lights and not other lights).

 

I will check on that this week coming weekend I will check the fuse first and go from there thank you very much I will keep you posted