Chassis
generic / SAE
C058D
Brake Booster Motor B Position Sensor Circuit High
Booster motor A position sensor signal voltage above expected range. Boost control tracks commanded vs. actual manifold pressure; persistent deviation means wastegate, vanes, hose or actuator are not delivering the requested pressure.
SystemChassis
Typegeneric / SAE
GroupC0
Range / number5 / 8D
Possible causes
- Signal wire shorted to battery high
- Connector pins corroded - high contact resistance low
- Supply wire pinched against B+ source low
Symptoms
- ABS warning light on
- ESC/stability control deactivated
- Possible reduced brake assist
- Speedometer may behave erratically
Inspection / repair
- Difficulty: hard
- DIY: shop recommended
- Estimated cost: 200–1500 €
- Estimated time: 1–5 h
- Component: booster motor b pos sensor
- MIL / check engine light
- limp mode possible
Sources
References
sae:J2012