I have a 95 Z71 4x4 350 with an ABS light on. I replaced the right front wheel speed sensor before I knew how to pull the codes because the wire appeared to be damaged but the light is still on. When I did figure out how to pull the codes I found ABS codes 25,26,27 (all pertain to the left front wheel speed sensor)
code 37 which is erratic vehicle speed sensor
code 68 which is locked motor or shorted motor circuit
and code 88 which is shorted brake lamp warning.

Before I replaced the left front speed sensor I would like to know how do I test the electronic brake control module? I have heard that these units sometimes go bad on these trucks. Also can these be rebuilt? I am on a budget. Thanks for your input.

 

ABS has never been one I have messed with. Good luck...