ABS Light On

[va350]

Having problems diagnosing this issue. I recently replaced my master cylinder which took care of my original problem but after replacing it the ABS light came on and I can't get it to go out. Almost everything is new in the brake system; I've recently replaced rear shoes, drums and cylinders; front pads, rotors and calipers. After the ABS light came on I replaced the RABS hydraulic valve. I am trying to pull the RABS codes but can't get the light to flash the codes. I've grounded the black/orange cable under the dash and nothing happens, the light just stays lit. Any suggestions on what to do next or how to pull the codes. I was going to re-adjust the rear brake shoes this weekend and bleed the lines again.

 

['94IDITurbo7.3]

sorry i don't have any tech to add, but you could just unplug the abs computer. honestly the abs systems on these truck sucks. rather than "pumping" the breaks for you, our system just dumps pressure in the rear system. i've driven on some gnarly ice with my truck w/o abs and i never had a problem.

 

[va350]

I just noticed your from Fowlerville Michigan. I had to look on mapquest to see where that was, it sounded familiar. I'm from Lake Orion.

 

['94IDITurbo7.3]

cool. my aunt and uncle live out near there.

 

[va350]

I re-adjusted the rear brakes and bled the brakes again with the same results. Why can't I pull codes, could the control module be bad?

 

[OLDBULL8]

To pull the codes. With the engine running and the ABS light is on. With auto trans, put in PARK, with Manual, put in Neutral with Emerg. brake on. locate RABS diagnostic connector under the dash with Black/Orange wire, attach a jumper wire to it, momentarily touch ground, light should begin to flash, count all short flashes and one long flash at end of cycle, do that several times to get the correct code. Get code and report back, too many codes to list, 1 to 16 flashes, 1 and 16 are not used.

Try this to reset the dump valve, on the side of the ABS valve is a hex plug, unscrew it, take the spring out, leave the valve/piston in, replace plug, operate/apply the brakes several times, did the light go OUT, replace spring, operate/apply brakes, light should go OUT.

 

[va350]

I still can't pull the codes. I've made sure I have a good ground. The ABS list just stays lit, never flashes or goes out. I didn't try pulling the spring out of the valve but I just replaced the hydraulic valve.

 

[Fozz]

Does the truck stop ok? If I remember correctly, that can be an indicator of a vacuum pump going out (or vacuum leak). It's happened to both my trucks and then I had no brakes shortly thereafter...... vacuum pump had died on both.