P2526
Vacuum Reservoir Pressure Sensor Circuit Range/Performance
Vacuum reservoir / control system
Generic OBD-II
Medium
What it means
P2526 means the vacuum reservoir pressure sensor is reporting a value the computer considers implausible. That reservoir stores engine or pump vacuum used by systems such as the brake booster and various actuators. The fault is usually the sensor, its wiring, or a leaking hose rather than an engine problem, but it's worth diagnosing because the vacuum it monitors can support braking.
Medium
Can I keep driving? Usually driveable, but have it checked — on some vehicles this vacuum feeds the brake booster and other actuators, so don't leave it unresolved.
Common symptoms
What you'll notice
- Check-engine light on
- Weaker brake-pedal assist on vehicles that use this vacuum for braking
- Vacuum-actuated systems (HVAC flaps, actuators) not working as expected
- Often no obvious symptom
Common causes
Most likely first
- Faulty vacuum reservoir pressure sensorLikely
- Wiring open, shorted, or a poor connection at the sensorCommon
- Vacuum leak or a blocked/kinked hose to the reservoir skewing the readingCommon
- Less commonly, a failing ECM/PCMLess often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and view the live vacuum reading.
- Inspect the sensor connector and wiring for damage or corrosion.
- Check the vacuum hoses and reservoir for leaks, blockage, or a loose fit.
- Verify actual vacuum with a hand-held gauge and compare to the sensor value.
- Replace the sensor if it reads out of range, then clear and retest.
FAQ
Quick answers
Is it safe to drive with P2526?+
Usually yes, but on vehicles where this vacuum assists the brakes you may notice a firmer pedal. Have it checked soon rather than leaving it.
Can I just clear P2526?+
It comes back if the sensor or a vacuum leak is still present. Diagnose the circuit and hoses first.
Related codes
Often seen with P2526
Read & clear P2526 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX