GM-GMC: brake lights wont flash when brake is applied, gmc sierra, brake fluid

Question
Hello Alicia, i have a problem with my GMC sierra 1500 its a 1994 with 115k miles on it, 5.0. My problem is my brake lights  wont come on when i tap my brake. I checked the bulbs they are fine (i just had new park/rear/front lights installed) i also checked brake fuse,stop fuse, flinker fuse, they are all fine. I know i need to change my brake fluid soon could that be the problem? Just please try to least me all reasons why this could happen and any possible solutions to them, thanks anyways.

Answer
i assume you are saying no break lights at all and if you just had them replaced that means there is a wire that is not properly connected..

because honestly if you have already checked what you say you have checked those are it

bulbs
fuses
relays = the ones under the hood too
one more thing --> contact panel that is the panel that the bulbs plug into it is removable and is a common problem


i had to replace mine on a 99 suburban about 30 bucks...

when you take the lights off you will know what it is its just the black panel the bulbs plug into and the wiring plugs into the back of it...