OBD-II code · Chassis

C057F Brake Booster Motor A Phase U-V-W Circuit/Open

Open circuit on one of the three U/V/W phases of brake booster motor A (3-phase BLDC motor in electric brake boosters).

Is it safe to drive with C057F?

The car may go into limp mode (reduced power). Get it diagnosed before a long trip.

Common causes

  • Most likelyPhase wire open or motor winding 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
Hard
DIY friendly
Best left to a mechanic
Typical labour
2–6 h
Emissions test
Usually unaffected
Parts involved
Brake Booster Motor A, Motor Phase Wiring

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