OBD-II code · Chassis
C05CF Brake Master Cylinder Piston Position Sensor B Circuit Range/Performance
Brake Master Cylinder Piston Position Sensor B Circuit Range/Performance: the signal is implausible or outside the valid range.
Is it safe to drive with C05CF?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelySensor reading drifted
- Less likelySensor element aged beyond calibration window
- Less likelySensor mounting loose - signal damping
Symptoms
- ABS warning light on
- ESC/stability control deactivated
- Possible reduced brake assist
- Speedometer may behave erratically
Repair at a glance
- Difficulty
- Hard
- DIY friendly
- Best left to a mechanic
- Typical labour
- 1–5 h
- Emissions test
- Usually unaffected
- After the fix
- A drive cycle is needed before the light stays off
- Parts involved
- Master Cylinder Pos Sensor B
Related codes
- C05CCBrake Master Cylinder Piston Position Sensor A Circuit Range/Performance
- C05CDBrake Master Cylinder Piston Position Sensor B Circuit Voltage High
- C05CEBrake Master Cylinder Piston Position Sensor B Circuit Voltage Low
- C05D0Brake Master Cylinder Piston Position Sensor A/B Correlation
- C05D1Brake Master Cylinder Piston Position Sensor Supply Circuit
- C05D2Master Cylinder Piston Position Higher Than Expected
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.