P2527 moderate

Vacuum Reservoir Pressure Sensor Circuit High

The P2527 code means the vehicle's onboard diagnostic system has detected: Vacuum Reservoir Pressure Sensor Circuit High. This is a moderate severity code.

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Keep driving?: Yes, but fix soon
DIY difficulty: moderate
Estimated cost: $80 - $300 (parts and labor)

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Common Symptoms

Check engine light on
Inaccurate vacuum system monitoring
HVAC system may operate erratically
No noticeable drivability issues

Probable Causes (Ranked by Likelihood)

Faulty sensor reading higher than actual vacuum Very High
Short to voltage in sensor signal wire High
Sensor reference voltage supply issue Moderate
ECM input circuit fault Low

Step-by-Step Diagnostic Procedure

Compare sensor reading to manual vacuum gauge
Check sensor signal wire for short to power
Test sensor 5V reference supply voltage
Inspect sensor connector for bent or backed-out pins

Frequently Asked Questions

Is P2527 dangerous?

Not immediately. The vehicle may not accurately monitor vacuum levels, but brake assist typically still functions. Repair to ensure proper system monitoring.

What voltage should the vacuum sensor read?

Typically 0.5V to 4.5V proportional to vacuum level. P2527 sets when the voltage exceeds the expected range for current conditions.

Can I test the sensor myself?

Yes, with a multimeter. Measure the signal voltage at the sensor connector and compare it to the 5V reference. A reading near 5V with vacuum present indicates a faulty sensor or wiring.