Powertrain, generic (extended)

P2C25 Exhaust Heat Exchanger Exhaust Bypass Valve A Position Sensor Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modeNo

P2C25 is the counterpart of P2C24: the feedback from the position sensor of exhaust heat exchanger bypass flap A sits above the highest value a working sensor can deliver. This usually points to a signal line touching a voltage source, an interrupted sensor ground or an internal sensor fault that pulls the output toward the reference. The check is a pure range test demanded by CARB for comprehensive components and does not judge whether the flap actually moves. No manufacturer documents P2C25 publicly; the nearest cases are Ford's full hybrids, where SSM 52050 fixes P2C22/P2C23 on F-150 PowerBoost trucks with a new muffler inlet pipe, naming the bypass valve as cause. Ford's patent describes estimating the flap state from coolant temperatures instead. Expect a lit MIL and reduced heat recovery.

Likely causes

Position signal wire shorted to a voltage source
Open ground circuit of the position sensor
Position sensor in the actuator failed high

Symptoms

  • Check engine light
  • Cabin heater slow to warm up in winter

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€80–1,200
Time0.5–3 h

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

Parts involved

exhaust heat exchanger bypass valve a pos sensorwiring harnessecm

Related codes

P2C22P2C23P2C24P237E

References: law.cornell.edu, static.nhtsa.gov, patents.google.com.