Mike's Workshop Manuals: Service manuals for every vehicle
Home >> GMC >> 1998 >> Forward Control 6.5 F >> Repair and Diagnosis >> Brakes >> Traction Control >> Anti-Lock Brake System >> Diagnostic Tests >> DTC C0221: Right Front Wheel Speed Sensor Circuit Open >> Circuit Description

Circuit Description

As a toothed ring passes by the Wheel Speed Sensor (WSS), changes in electromagnetic field cause wheel speed sensor to produce an AC voltage signal. Voltage signal frequency and amplitude are proportional to wheel speed. The magnitude of this signal is directly related to wheel speed and proximity of wheel speed sensor to toothed ring, often referred to as the air gap.

Conditions for setting DTC: