Powertrain, generic (extended)

P2526 Vacuum Reservoir Pressure Sensor Circuit Range/Performance

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible

P2526 marks a vacuum reservoir pressure reading that stays inside the electrical range but does not fit the situation, for instance no rise in vacuum after the pump has run, or a value frozen while actuators draw on the reservoir. Because the sensor watches a real system, genuine vacuum faults such as a leaking hose, a worn pump or a cracked reservoir can set it as well as a drifting sensor. Two makers name it. FCA lists P2526 among the codes the revised engine software may newly log after emissions recall T21 on the 2004–2006 Dodge Sprinter. Hino's 2019 bulletin SB-19-013 for J05E cab-over trucks has technicians clear P2526 first before working through exhaust brake fault P0027, which uses vacuum-driven valves. Thresholds stay unpublished. Electrical faults are P2527–P2529.

Likely causes

Leaking vacuum hose, check valve or reservoir
Mechanical or electric vacuum pump delivering too little
Pressure sensor drifting or stuck

Symptoms

  • Check engine light, often with boost or EGR codes
  • Weak exhaust brake or reduced power
  • Hissing noise from a leaking line

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€40–600
Time0.5–3 h

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

Parts involved

vacuum reservoirvacuum reservoir pressure sensorvacuum linesvacuum pump

Related codes

P2525P2527P2528P2529P0027

References: static.nhtsa.gov, static.nhtsa.gov, law.cornell.edu, en.wikipedia.org.