OBD-II code · Chassis
C057B Brake Booster Temperature Sensor B Circuit/Open
Open circuit on brake booster temperature sensor B. Boost control tracks commanded vs. actual manifold pressure; persistent deviation means wastegate, vanes, hose or actuator are not delivering the requested pressure.
Is it safe to drive with C057B?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelySignal wire open
- Less likelyPin pushed back out of connector body
- Less likelyCracked solder joint inside the module or sensor
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
- Best left to a mechanic
- Typical labour
- 1–4 h
- Emissions test
- Usually unaffected
- Parts involved
- Brake Booster Temp Sensor B
Related codes
- C05B5Brake Booster Temperature Sensor C Circuit/Open
- C0578Park Brake Switch Stuck Open
- C0579Brake Booster Temperature Sensor B Circuit Low
- C057ABrake Booster Temperature Sensor B Circuit High
- C057CBrake Booster Temperature Sensor B Circuit Range/Performance
- C057DBrake Booster Temperature Sensor Circuit B Intermittent/Erratic
- C057EBrake Booster Temperature Sensor A/B Correlation
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.