Brake Booster Pressure Sensor
Confirms sufficient vacuum is available to assist the brakes, and on many vehicles triggers a vacuum pump on demand. Worth understanding what happens when the vacuum genuinely is absent rather than merely unmeasured: the brakes still work, but the pedal becomes very hard and stopping distances lengthen considerably — a serious surprise if discovered during an emergency stop rather than in a car park.
Also known as: brake vacuum sensor, booster pressure sensor, brake booster sensor, vacuum sensor
Referenced by 39 codes
Codes involving this component (39)
- C0021 Brake Booster Performance High
- P0555 Brake Booster Pressure Sensor Circuit High
- P0556 Brake Booster Pressure Sensor Circuit Range/Performance High
- P2525 Vacuum Reservoir Pressure Sensor Circuit High
- P2526 Vacuum Reservoir Pressure Sensor Circuit Range/Performance High
- P2527 Vacuum Reservoir Pressure Sensor Circuit Low High
- P2528 Vacuum Reservoir Pressure Sensor Circuit High High
- P2529 Vacuum Reservoir Pressure Sensor Circuit Intermittent High
- P258B Vacuum Pump Control Circuit A Range/Performance High
- U0129 Lost Communication With Brake System Control Module A High
- U0318 Software Incompatibility With Brake System Control Module A High
- U0418 Invalid Data Received From Brake System Control Module A High
- C0047 Brake Booster Pressure Sensor Moderate
- P0557 Brake Booster Pressure Sensor Circuit Low Input Moderate
- P0558 Brake Booster Pressure Sensor Circuit High Input Moderate
- P0559 Brake Booster Pressure Sensor Circuit Intermittent Moderate
- C0547 Vacuum Sensor Supply Voltage Circuit/Open
- C0548 Vacuum Sensor Supply Voltage Low
- C0549 Vacuum Sensor A Circuit/Open
- C054A Vacuum Sensor A Range/Performance
- C054B Vacuum Sensor A Circuit Low
- C054C Vacuum Sensor A Circuit High
- C054D Vacuum Sensor B Circuit/Open
- C054E Vacuum Sensor B Range/Performance
- C054F Vacuum Sensor B Circuit Low
Other components in Electrical and Charging
- Data Bus 563
- Battery 218
- Gateway Module 158
- Stability Control Module 122
- Battery Temperature Sensor 115
- Infotainment Head Unit 49
- Alternator 45
- A/C Refrigerant Pressure Sensor 33
- Brake Light Switch 32
- Cruise Control Switch 31
- Ignition Switch 31
- Cooling Fan Relay 28
- Starter Relay 25
- A/C Compressor 25
- Clutch Switch 24
- ECM Power Relay 21
- Roof Antenna Module 19
- Immobiliser 15
- Lighting Driver Control Module 15
- Starter Motor 14
- Transmission Control Module Power Relay 14
- Fuel Pump Relay 13
- Secondary Air Injection Relay 13
- Battery Monitoring Sensor 10
- Driver Information Centre 10
- A/C Evaporator Temperature Sensor 8
- Telematics Control Module 8
- Navigation Control Module 6
- Headlamp Levelling Actuator 6
- Hydraulic Pump Relay 5
- Head-Up Display 2
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