Some 2021 F-150 vehicles equipped with a 3.3L or 5.0L engine, Transit vehicles equipped with a 3.5L Duratec engine, and Explorer/Police Interceptor Utility vehicles equipped with a 3.3L engine may exhibit an illuminated malfunction indicator lamp (MIL) with diagnostic trouble code (DTC) P0106 stored in the powertrain control module (PCM) after key-off transportation of the vehicle to higher altitudes. To correct the condition, clear the DTCs, cycle the ignition to OFF, cycle the ignition to ON, wait ten seconds, cycle the ignition to OFF, wait ten seconds, then start the engine. If the condition remains, refer to the Powertrain Control/Emissions Diagnosis (PC/ED) Manual for diagnostics.