C05A4 Wheel Speed Sensors Supply Circuit Low
What does C05A4 mean?
C05A4 — Wheel Speed Sensors Supply Circuit Low. This is an OBD-II diagnostic trouble code a scanner retrieves when your vehicle's computer detects wheel speed sensors supply circuit low. The level of risk depends on how the vehicle is currently running and how long you've been driving with the light on.
Common causes of C05A4
- Faulty wheel speed or chassis sensor
- Damaged wiring, connector, or corrosion in the sensor circuit
- Worn wheel bearing or damaged tone ring affecting the sensor gap
- Chipped or contaminated sensor reluctor wheel
- Failed ABS or chassis control module
How to fix C05A4
These are general steps for this system. The exact cause depends on your vehicle — confirm with live scan data before replacing parts.
- Scan the chassis/ABS module for specific fault codes
- Inspect the affected sensor, wiring, and connector
- Read individual wheel speeds with an OBD-II scanner during a roll test
- Check the wheel bearing and reluctor ring condition
- Replace the failed sensor or component after circuit tests