Powertrain, generic (extended)

P237F Exhaust Heat Exchanger Exhaust Bypass Valve A Control Performance

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

P237F is not about wiring of the drive but about the result: the bypass flap A of the exhaust heat recovery unit was commanded, yet the effect the module expects does not appear. Ford judges this partly by temperatures, which is why SSM 52543 for the full hybrids F-150 3.5L (from 2021), Explorer 3.3L and Escape 2.5L (from 2020) and Maverick 2.5L (from 2022), all through 2024, first sends technicians to the connectors of exhaust coolant temperature sensors 3 and 4 – damaged seals, corrosion or water there can set P237F without a bad valve, so the heat exchanger need not be replaced. TSB 24-2173 fixes false P237F on 2024 Mavericks built up to 10 April 2024 with a PCM update. SSM 53003 covers a worn actuator on the F-150. The MIL comes on, driving is unaffected.

Likely causes

Water, corrosion or torn seal at the exhaust coolant temperature sensor 3/4 connectors (Ford SSM 52543)
PCM calibration setting the code falsely (2024 Maverick, TSB 24-2173)
Bypass actuator or flap sluggish, sticking or worn

Symptoms

  • Check engine light on
  • No effect on drivability
  • Often stored together with P2C23

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€0–1,500
Time0.5–3 h

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

Parts involved

exhaust bypass valve aexhaust bypass position sensor aexhaust heat exchanger

Related codes

P237CP237DP237EP23A5P2C23P2C22

References: static.nhtsa.gov, static.nhtsa.gov, static.nhtsa.gov.