C0120high severityChassis
Electronic Parking Brake Motor Circuit
on 2016 GMC Sierra 1500 5.3L V8 · 4WD
What this code means
Malfunction in the electronic parking brake actuator motor circuit.
Symptoms
- Parking brake warning light
- EPB will not apply or release
- Audible grinding from rear brakes
- Hill-hold assist inoperative
Common causes
- EPB motor failure
- Wiring to EPB motor damaged
- EPB module failure
- Motor connector corroded
Diagnostic steps
- Test EPB motor by commanding apply/release with scan tool
- Check motor connector for corrosion
- Test motor winding resistance
- Inspect wiring harness
- Check EPB module outputs
Repair notes
Replace EPB motor/caliper assembly. EPB systems typically require scan tool for service mode before pad replacement.
Other Chassis codes on this vehicle
C0021
LF Wheel Speed Sensor Range/Performance
C0022
RF Wheel Speed Sensor Range/Performance
C0023
LR Wheel Speed Sensor Range/Performance
C0024
RR Wheel Speed Sensor Range/Performance
C0025
LF Wheel Speed Sensor Circuit Intermittent
C0026
RF Wheel Speed Sensor Circuit Intermittent
C0027
LR Wheel Speed Sensor Circuit Intermittent
C0028
RR Wheel Speed Sensor Circuit Intermittent
C0035
Left Front Wheel Speed Sensor Circuit
C0036
Left Front Wheel Speed Signal Erratic