Some 2024 F-150 Lightning vehicles may set diagnostic trouble code (DTC) U0594:68 in the heat pump valve control module (HPVCM) when a diagnostic self-test is performed. This may be due to HPVCM sensitivity while in accessory mode. DTC U0594:68 has no effect on functionality and will automatically become a historical DTC which can be cleared. Replacement or reprogramming of the HPVCM will not resolve this condition. DTC U0594:68 should be ignored if no other DTCs are present in the HPVCM, no warning indicators are illuminated while the vehicle is on, and no symptoms present. No further service action is required.
