C0123high severityChassis
Electronic Parking Brake Control Module
on 2010 Mazda Mazda3 2.5L I4 · FWD
What this code means
Internal fault in the electronic parking brake control module.
Symptoms
- EPB warning light on
- EPB functions inoperative
- Hill-hold not working
- Auto-hold not functioning
Common causes
- EPB module internal failure
- Module software corruption
- Power supply issue to module
- CAN communication fault to module
Diagnostic steps
- Check module power supply and ground
- Scan for CAN communication codes
- Attempt module reset
- Check for software updates
- Test module inputs and outputs
Repair notes
Replace EPB control module. Requires programming and calibration.
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