I have a 1990 s10 blazer 4x4 2 door and my break lights wont turn off even when the truck is off.
I metered out the break switch all good there re calibrated it as specifyed by the book I went even went so far as to replace the hazard and signal switch thing in my steering column (which according to the wiring diagram interacts with the break lights via hazard switch) thinking it might be bad. and I have no idea what to do now, should i replace the flasher relays for hazard and signal lights? which could be the only other things feeding power to those light's according to the diagram unless there's a short in my wiring harness some were but i have no idea what wires are what in there cause i cant find jack **** on the internet.
The really funky thing is when i turn on my left or right signal light the right break light turns off but not the left one. no idea wtf is happening to cause this. by the way neither signal light works it just messes with that right break light

 

Sounds like you may have electrical problems under dash near steering wheel.

 

Yep check behind the arm on the brake peddle, there is a switch there