I'm having a problem, with my braking system, which i am trying to take care of myself. When i start the truck, the brake light and abs light come on as usual, but then the abs light goes off and comes back on, and will stay on along with the brake light, until you turn the truck off. I don't know why, i've tried testing for codes myself, and the codes will not flash on at all, there is a black w/ a orange stripe wire which i ground, but still no codes, also i'm not dumb, the rotors and pads in front are new, the brakes in back still have a 1/4 inch on the pads, and the brake fluid is filled, and the floating sensor, is moving. I've also tried testing the ohms on the speed sensor mounted on the differential, which is reading 32,000 ohms off the wire when off and reading 1000 ohms while it is on. any suggestions? the brakes stop just fine, so right now, the light is just annoying me. Could it be the master cylinder going out? a bad RABS valve, bad RABS sensor, or possible the RABS module just went out, and thats why the codes swon't come on, and the light is continuously lit.