LINCOLN · 2025-11-25
Some 2025-2026 Nautilus vehicles with heated-only front seats (minor feature code BY1AC) (not heated and cooled) may set diagnostic trouble codes (DTCs) B103A:15, B1034:13, B1036:13, and B1038:15 in the heating, ventilation, and air conditioning (HVAC) module when a diagnostic self-test is performed. These DTCs have no effect on functionality and should be ignored if no other DTCs are present in the HVAC module and no symptoms are present. Continue with diagnosing any other HVAC DTCs first. No further service action is required.<br /><br /> To confirm a vehicle is built with a certain minor feature code, review the build information by double-clicking the vehicle identification number (VIN) in the upper left corner in the Professional Technician System (PTS).