C0547
Vacuum Sensor Supply Voltage Circuit/Open
Open circuit on the vacuum sensor supply voltage line. Vacuum sensors are used in vacuum-assisted brake boosters to monitor manifold or booster vacuum.
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: medium
Symptoms
- ABS warning light on
- ESC/stability control deactivated
- Possible reduced brake assist
- Speedometer may behave erratically
Common causes
Ordered by how often each turns out to be the cause.
- Supply wiring openCommon
- Pin pushed back out of connector bodyLess likely
- Cracked solder joint inside the module or sensorLess likely
Parts involved
- Vacuum Sensor
- Sensor Supply
C0547 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.