The TrailBlazer, originally introduced as an upscale Blazer, was produced from 2002 to 2008 with a powerful I6 engine and with a monster V8 offered in the Trailblazer SS
Platform: GMT 305, 360, & 370.
If both arent working at the same time, then its the fuse. And if you say the fuses are fine, then I'm willing to believe you. So it has to be a bad contact somewhere.
Try the hand brake (or however you call the brake that you use while parking the car). If that turns the lights on, then you might want to check the cables leaving your brake pedal. One of them might be disconnected.
tried the hand brake no change. I read another post on a chevy truck and it mentioned the brake light switch. My cruise has stopped working also. Won't engage at all. Didn't connect the cruise not working to the brake lights even though the brake switch does control both. Is this possible. If so is it difficult to change?
If you are measuring voltage at the brake switch. I believe there is an orange wire that will have 12v at all time, and a white wire that has 12 volts while the brake is depressed.
If the orange wire has no voltage, chack for a broken wire or blown fuse, if there is no voltage on the white wire when the brake is pressed, and the orange wire does have voltage, then the switch is bad.
If you have a question, ask it in the forums. I will no longer be answering questions sent to my email.
2002 ltz t blazer brake lites keep blowing bulbs any help please
I had a similar issue on my 03 TB several years ago and found there was a recall for this problem. I took it in and they replaced both sides. The problem started again a year or so later. I disconnected the battery and cleaned the sockets on both sides with alcohol. I had to replace a backup bulb about 6 months ago but no other issues.
I have not seen the issue the OP had but something is causing the circuit to draw to much current and I would suggest checking the connections on the brake light assemblies. I thought they used to much contact grease which is why I cleaned them with alcohol and did not put any back.