Chassis, generic

C05C1 Brake Pedal Position Sensor B Not Learned

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modePossible

Set when the second, redundant channel B of the brake pedal position sensor lacks a stored zero point. Many electric and hybrid brake pedals read travel twice so that one channel can cross-check the other; Bosch builds such pedal travel sensors with a magnetic field sensor and two redundant outputs. Without a learned rest value for B, that cross-check is lost even when channel A is fine. No manufacturer publishes C05C1. GM handles the comparable fault as C0277-4B and simply recalibrates, and Hitachi only accepts a new zero if the complete learn run finished without pedal input. After fitting a new pedal sensor or control unit, run the learn with the pedal fully released. C05C0 is the twin for channel A, C061A the offset-limit fault.

Likely causes

Channel B not learned after a repair or software update
Learn conditions not met (pedal pressed, vehicle rolling)
Channel B of the pedal sensor faulty or out of tolerance

Symptoms

  • Brake warning lamp or service message
  • Reduced redundancy, some assist or regeneration functions disabled

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€50–400
Time0.3–1.5 h

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

Parts involved

brake pedal sensor bbrake control module

Related codes

C05C0C061AC0277C05D4

References: eenewseurope.com, patents.google.com, saabwisonline.com.