Chassis, generic

C0541 Brake Pressure Sensor B Range/Performance

Check engine lightUsually off
EmissionsNot relevant
Drive cycleRequired
Limp modePossible

Brake pressure sensor B delivers a valid voltage, yet the value is implausible. Which sensor carries the letter B varies by maker. Bentley documents the code for the Continental GT/GTC (2018–2022) and Flying Spur (2020–2022): C054100 in the ESC unit J104 is labelled as a fault of the rear-left pressure sensor, adaptive cruise control becomes unavailable, and the repair is a new J104 because the sensor is built into it. Typical tests behind such a fault are described by Saab, whose 9-5 brake module rejects a pressure reading that does not match deceleration or the brake switch, and by a Honda patent that declares the sensor failed when pedal stroke grows but pressure does not. A Bosch patent adds an offset that has drifted too far. C0542 to C0544 are the electrical faults.

Likely causes

Pressure sensor inside the ESC hydraulic unit drifting or sluggish
Zero-point calibration not done after module or valve block replacement
Brake light switch or pedal sensor giving a contradictory reference

Symptoms

  • Adaptive cruise control unavailable
  • ESC or ABS warning in the cluster
  • Assistance functions such as brake assist reduced

Repair estimate

DifficultyHardWorkshop job
Parts and labour€100–2,500
Time0.5–3 h

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

Parts involved

brake pressure sensor b

Related codes

C0542C0543C0544C053D

References: static.nhtsa.gov, saabwisonline.com, patents.google.com, patents.google.com.