Vacuum Reservoir Pressure Sensor Circuit Low
What it means
P2527 means the vacuum reservoir pressure sensor is sending a signal that's too low, usually from a wiring short, an open circuit, or a failed sensor. The reservoir stores vacuum for systems like brake assist and emissions actuators, so the fault mainly affects those functions rather than how the engine runs.
Can I keep driving? Usually drivable, but systems that rely on stored vacuum — such as brake assist or emissions actuators on some vehicles — may not work correctly, so have it checked.
Real-world scan data
Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.
Common symptoms
What you'll notice
- Check-engine light on
- Vacuum-operated systems may behave inconsistently
- Possible harder brake pedal on vehicles that use the reservoir for brake assist
- Often no obvious driving symptom
Common causes
Most likely first
- Faulty vacuum reservoir pressure sensorLikely
- Short to ground or open in the sensor's signal wiringCommon
- Corroded or loose sensor connectorCommon
- Loss of the 5-volt reference or ground to the sensorLess often
- Cracked or leaking vacuum lines to the reservoir affecting the readingLess often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and check the sensor's live reading with a scan tool.
- Inspect the sensor connector and wiring for a short to ground, an open, or corrosion.
- Verify the reference voltage and ground at the sensor connector.
- Check the vacuum lines and reservoir for leaks or blockage.
- Replace the sensor if its signal stays low with good wiring, then clear and re-test.
FAQ
Quick answers
Is it safe to drive with P2527?+
Can I just clear P2527?+
Related codes
Read & clear P2527 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.