Some 2018-2019 Ford Mustangs built on or before Oct. 17, 2018, with a 2.3L EcoBoost engine and operating in altitudes of 3,500 feet above sea level and higher may exhibit an illuminated MIL with only DTC P0069 stored in the PCM.
Using the appropriate diagnostic tool, retrieve DTCs. If the only DTC stored is P0068, reprogram the PCM using the latest software version. This will recalibrate for the thinner air conditions found at high altitudes.
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