P2527
Vacuum Reservoir Pressure Sensor Circuit Low
Sensor signal voltage below the lower limit — usually a short to ground or open reference. The ECM disables vacuum pump control until the input recovers.
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: medium
Common causes
Ordered by how often each turns out to be the cause.
- Signal wire shorted to groundCommon
- Missing 5 V reference at the sensorPossible
- Connector pins corroded - high contact resistanceLess likely
Parts involved
- Vacuum Reservoir Pressure Sensor
- Sensor Wiring
P2527 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.