Brake light on, spongy pedal, HELP!!

[Chris Hays]

I own a 1992 chevrolet K1500 Xtended cab 350 with the RWAL brakes system on it. The truck was parked for seven weeks, when i came back the brake light was on and the pedal went nearly to the floor. I assumed that a seal in the master cylinder may have got stuck and broke so i replaced that, no fix the problem!! Next i checked the codes which said faulty dump valve so i replaced this with one from a junkyard, didnt fix it. Next i also replaced the combination valve and the computer module from a junkyard truck this still is the same. I have replaced all the rear brake components, cylinders, pads, adjusters, springs, everything in their.E ventually i read an article about how remanufactured master cylinders are not worth a d**n so this is what i think it might be. Right now i have nearly no pedal at all and i have bled the system over and over. The only thing i did that made a difference was to take the line that goes from the bottom of the dump valve and screw it straight in to the combination valve, This made a difference and it stoped a lot better, but i cant get the brake light to go off!! ANY IDEAS????

[budhayes3]

If the master is full of fluid and the light is still on, the brake fluid level sensor may be stuck. As far as the spongy pedal goes, check for leaks and swollen brake lines. Be sure to check the front caliper slide pins also. If a slide pin is siezed, it will make the pedal feel spongy like a hydraulic problem, even though it's a mechanical problem.