Powertrain, generic (extended)

P26C1 Engine Coolant Bypass Valve D Range/Performance

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

P26C1 means valve D works electrically but does not deliver the expected effect. Ford is the documented user, and on its plug-in hybrids valve D governs the cabin heating loop. Ford special service message 50325 and bulletin 22-2127 cover 2020–2022 Escape and 2021–2022 Corsair PHEVs that set P2183 for the second coolant temperature sensor, at times with an overheat warning; P26C1 can follow as a consequence. The root cause was a PCM soak timer that miscalculated how long the electric cabin heater had been off, so the fix is reprogramming several modules, starting with the PCM; checking coolant level and the ECT 2 connector came first. Ford's public summaries give no thresholds for P26C1. Diagnose P2183 before replacing the valve.

Likely causes

PCM software miscalculating heater soak time (Ford PHEV)
Contaminated connector of coolant temperature sensor 2
Valve D moving slowly or sticking
Low coolant level

Symptoms

  • Check engine light
  • Engine overheat message in the cluster
  • P2183 stored at the same time

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€0–700
Time0.5–3 h

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

Parts involved

coolant bypass valve dthermostat housing

Related codes

P2183P26C0P26C2P26BD

References: static.nhtsa.gov, static.nhtsa.gov, fordservicecontent.com.