C0023 Code – ABS / Brake System Fault

The C0023 Diagnostic Trouble Code (DTC) is a manufacturer-specific chassis code related to the Anti-lock Braking System (ABS). The exact definition varies by vehicle manufacturer, but it is commonly associated with an ABS wheel speed sensor, brake booster, or ABS control circuit.

Common Symptoms

• ABS warning light ON.
• Brake warning lamp illuminated.
• Traction Control (TCS) or Stability Control (ESC) disabled.
• ABS may not operate during hard braking.

Possible Causes

• Faulty ABS wheel speed sensor.
• Open or short circuit in the sensor wiring.
• Loose or corroded electrical connector.
• Damaged wheel bearing tone ring.
• ABS control module fault.
• Low system voltage.

How to Diagnose

1. Read all ABS DTCs using a professional scan tool.
2. Check Freeze Frame and Live Data.
3. Compare wheel speed sensor values while driving.
4. Inspect wiring, connectors, and tone ring.
5. Measure sensor resistance and power supply if applicable.
6. Repair the fault, clear the code, and perform a road test.

C0023 Code Meaning by Vehicle Brand

Vehicle Brand	Typical Meaning
Subaru	Front Left Wheel Speed Sensor Circuit Fault.
GM (Chevrolet, GMC, Cadillac, Buick)	Brake Booster Solenoid or Brake System Circuit Fault (varies by model).
Chrysler / Dodge / Jeep / RAM	Manufacturer-specific ABS system fault.
Toyota / Lexus	ABS wheel speed sensor or brake actuator fault depending on model.
Ford / Lincoln	Manufacturer-specific ABS diagnostic code.
Honda / Acura	ABS system fault; exact definition varies.
Hyundai / Kia	Manufacturer-specific brake control system fault.
Volkswagen / Audi / Skoda / SEAT	Manufacturer-specific ABS or brake electronics fault.

Related DTCs

• C0020
• C0021
• C0022
• C0035
• C0040

Important: The definition of C0023 is manufacturer-specific. Always verify the exact description using the factory service manual or a professional scan tool before replacing any components.