OBD-II code · Chassis
C05C9 Brake Pressure Sensor Supply Circuit
Generic fault on the supply voltage shared between brake pressure sensors.
Is it safe to drive with C05C9?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelySupply wiring fault
Symptoms
- ABS warning light on
- ESC/stability control deactivated
- Possible reduced brake assist
- Speedometer may behave erratically
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Often, with basic tools
- Typical labour
- 0.5–2 h
- Emissions test
- Usually unaffected
- Parts involved
- Brake Pressure Sensor Supply
Related codes
- C05C6Brake Pressure Sensor F Circuit Low
- C05C7Brake Pressure Sensor F Circuit High
- C05C8Brake Pressure Sensor F Circuit/Open
- C05CABrake Master Cylinder Piston Position Sensor A Circuit Voltage High
- C05CBBrake Master Cylinder Piston Position Sensor A Circuit Voltage Low
- C05CCBrake Master Cylinder Piston Position Sensor A Circuit Range/Performance
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.