Electronic Parking Brake Control Module
2018-2018 Cadillac XT5 3.6L V6
The 2018 Cadillac XT5 is equipped with a 3.6L V6 engine. Below you'll find detailed c0123 diagnostic code information including labor time estimates, cost ranges, and technician notes specific to this engine configuration.
Description
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.
Related Codes
Other Chassis Codes
- C0021LF Wheel Speed Sensor Range/Performance
- C0022RF Wheel Speed Sensor Range/Performance
- C0023LR Wheel Speed Sensor Range/Performance
- C0024RR Wheel Speed Sensor Range/Performance
- C0025LF Wheel Speed Sensor Circuit Intermittent
- C0026RF Wheel Speed Sensor Circuit Intermittent
- C0027LR Wheel Speed Sensor Circuit Intermittent
- C0028RR Wheel Speed Sensor Circuit Intermittent
- C0035Left Front Wheel Speed Sensor Circuit
- C0036Left Front Wheel Speed Signal Erratic
C0123 on Other Vehicles
Common Questions
What does code C0123 mean on a 2018-2018 Cadillac XT5?
C0123 stands for "Electronic Parking Brake Control Module". Internal fault in the electronic parking brake control module.
What are the symptoms of C0123 on a Cadillac XT5?
Common symptoms of C0123 include: EPB warning light on, EPB functions inoperative, Hill-hold not working, Auto-hold not functioning.
What causes C0123 on a 2018-2018 Cadillac XT5?
Common causes of C0123 include: EPB module internal failure, Module software corruption, Power supply issue to module, CAN communication fault to module.
Last updated: March 2026