Hey I have a 1990 k1500. My brake light will not turn off. I brought it to a shop and they told me both wheel cylinders where blown. So I bought all new parts and put them in, with a brake flush. My light is still on, anyone know a possibility as to why?

 

Your problem is electrical, not mechanical.

If that brake light will flash when you turn your turn signal to that side, it's your Brake Switch.

If it won't, it still may be your Brake Switch, but, may also include the Turn Signal Switch.

I'd change out the Brake Switch first.

 

Brake light on the dash or the tail light?

 

Thanks both of you for replying. I didnt specifically say whether it was my tail lights or my dash. It is my dash. I had blown wheel cylinders, replaced both and redid both side brakes in the back. I can finally stop correctly, however my light on the dash has not gone off. It goes dim and goes away from time to time now, but it still comes on more than not.

 

I had the same problem with my 90. Brake light was on when I bought it over 10 years ago. Replaced the wheel cylinders as you did. Put new brakes and rotors on the front. One steel brake line rusted through so I replaced all of them. I sold it to a buddy and its still on. I have no idea why.

 

I have a 93 Suburban. The chilton's has a section on needing to "center the switch" after brake work to get the light off. It talks about holding a pin open on the combination valve and bleeding the rear brakes, then applying heavy pressure to the pedal to center the switch and turn the light off. It's in the section titled Combination Valve.