Chassis
generic / SAE
C05B4
Brake Booster Temperature Sensor C Circuit High
Brake booster temperature sensor C 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 / B4
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: medium
- DIY: shop recommended
- Estimated cost: 150–1200 €
- Estimated time: 1–4 h
- Component: brake booster temp sensor c
- MIL / check engine light
Sources
References
sae:J2012