I have a 1989 S10 Blazer with 4.3l.The one in my sig. My brake light came on, so I rebuilt the rear brakes which were in bad need of attention. My light is still on and since the light came on my cruise control does not release or turn off when i hit the brakes. My parking brake works well and when set the brake light gets brighter, when released the brake light gets dim but stays on. Can anyone please advise. As always thanx to all...

 

do you have that black box beside the master cylinder? my other 'Burb had the same issue. if you unplug that box, the light should go out completely (your PB being off of course).

as far as i know, the box controls the rear ABS on this era of truck. if the light keeps coming back on when it's plugged back in (could take upto 45 minutes for it to happen), then this is faulty.

while i never bothered to replace mine (truck was gone not too long after), i'm not 100% positive that this is a sure fire thing that the box is @ fault (maybe broken/damaged wires).

 

Is the master cylinder full?

 

The master cylinder is full. I will check the black box out soon as the monsoon blows thru Ky. Thanx