Miscellaneous Pcm Controls: Abs

On 4.3L "S" and "T" series equipped with M/T, a VCM computer also controls the Anti-Lock Brake System (ABS). VCM calculates wheel speeds through pick-up coils at each front wheel and VSS in rear of transmission. If lock-up is detected, VCM controls hydraulic valves and motors in Brake Pressure Modulator Valve (BPMV) assembly.

VCM is able to detect problems in the ABS related circuits and set trouble codes. For more information, see appropriate ANTI-LOCK BRAKE SYSTEM - 4-WHEEL article in BRAKES section.