SSM 52543

Some 2021-2024 F-150-3.5L FHEV, 2020-2024 Explorer 3.3L FHEV, 2020-2024 Escape 2.5L FHEV, and 2022-2024 Maverick 2.5L FHEV vehicles may exhibit an illuminated MIL with DTC P237F and/or P2C23 stored in the powertrain control module (PCM) and no affect on drivability. This may be due to seal damage, corrosion and/or water intrusion in the exhaust coolant temperature (ECT) sensors 3 and/or 4 connector. Visual inspection should be completed on ECT3 and ECT4 sensors and mating connections for seal damage, water intrusion, and corrosion. If seal damage, water intrusion or corrosion is present, repair per cell 5 of the Wiring Diagram, then apply Motorcraft® XG-12 Electrical Grease to the female/vehicle side of the harness. This inspection of ECT3 and ECT4 sensors should be completed prior to starting the appropriate pinpoint test in Section 303-03 of the Workshop Manual (WSM). If DTCs P237F and/or P2C23 do not return, no further action is necessary and the replacement of the entire exhaust heat exchanger assembly is not required. If P237F and/or P2C23 returns, follow the pinpoint test in Section 303-03 of the WSM for further diagnostics.