C056D: Brake Pedal Position Sensor Supply Voltage Circuit Low
Standardized SAE J2012 code · C05xx codes
Safety-critical system. Faults in airbags, brakes, steering or high-voltage components can put people at risk. Follow the manufacturer's service information and safety procedures, or have the vehicle checked by a qualified workshop.
What does C056D mean?
Brake pedal position sensor supply voltage below expected range. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
The code tells you which monitor failed, not which part is broken. Test before replacing parts.
Symptoms
- ABS warning light on
- ESC/stability control deactivated
- Possible reduced brake assist
- Speedometer may behave erratically
Common causes
- High Supply wire shorted to ground
- Low Connector pins corroded - high contact resistance
- Low Harness chafing through insulation
Likelihood is a general estimate across vehicles; your make and model may differ.
Add your car to see reports of C056D on the same make and model first.
C056D in the community
Ask about C056DNo one has posted about C056D yet
Share your vehicle, the tool you used and what you tested — the first thread helps everyone who searches for this code.
Describe your C056D problem