P2528 Vacuum Reservoir Pressure Sensor Circuit High

P2528 is logged when the vacuum reservoir pressure sensor delivers a voltage near or at its supply, beyond anything the sensing element can output. A signal wire touching 5 V or battery voltage, a broken sensor ground, or corrosion bridging pins in the connector are the classic findings. A real loss of vacuum does not normally push the signal this far; it would appear as a range or performance fault instead. No vehicle maker documents P2528 publicly, so this rests on CARB's demand that comprehensive component inputs be checked for circuit faults, and on how such reservoirs work: a pump, often on the camshaft of diesels and hybrids, keeps them evacuated for the brake booster and actuators. P2527 is the low extreme, P2529 an intermittent signal. Expect default actuator control.

Likely causes

Symptoms

• Check engine light depending on maker
• Reduced power with actuators in default position

Repair estimate

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

Related codes

References: law.cornell.edu, en.wikipedia.org.