C0221 BUICK Right Front Speed Sensor or Circuit Open

Possible causes
– Faulty Right Front Speed Sensor
– Right Front Speed Sensor harness is open or shorted
– Right Front Speed Sensor circuit poor electrical connection
– Faulty EBCM
Symptoms
– ABS Warning Light ON
C0221 BUICK OBD Code Description

As the wheel spins, the wheel speed sensor produces an Alternating Current (AC) signal. The Electronic Brake Control Module (EBCM) uses the frequency of the AC signal to calculate the wheel speed.