OBD-II code · Chassis

C057C Brake Booster Temperature Sensor B Circuit Range/Performance

Brake booster temperature sensor B reading implausible. 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 C057C?

Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.

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
Medium
DIY friendly
Best left to a mechanic
Typical labour
1–4 h
Emissions test
Usually unaffected
After the fix
A drive cycle is needed before the light stays off
Parts involved
Brake Booster Temp Sensor B

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.