Chassis, generic

C0570 Brake Booster Travel Sensor Circuit High

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modePossible

C0570 is the high-side counterpart of C056F: the booster travel signal reads above its plausible maximum. Typical triggers are a signal wire touching the 5 V reference line or battery positive, or a broken sensor ground that lets the input float upward. Travel sensing in boosters dates back to vacuum units in which an electrical sensor in the housing reported the position of the movable wall and had to be set against housing tolerances; electromechanical units like the iBooster measure pedal travel with a sensor inside the unit instead. No manufacturer documents C0570 publicly. A value stuck at the top can look like a fully pressed pedal, so the module normally disables electric assist and brake assist; stopping then needs much more pedal effort.

Likely causes

Signal wire shorted to the 5 V reference or to battery voltage
Open sensor ground letting the signal float to the upper limit
Travel sensor damaged internally, e.g. after water ingress at the booster
Wrong or not properly installed booster or sensor after a repair

Symptoms

  • Electric brake assist switched off, pedal much harder
  • Brake warning and stability control lamp on
  • Driver assistance braking functions disabled

Repair estimate

DifficultyHardWorkshop job
Parts and labour€80–2,500
Time0.5–4 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

brake booster travel sensorsensor wiring

Related codes

C056FC0048C056EC05CF

References: us.bosch-press.com, patents.google.com, patents.google.com, bosch-mobility.com.