As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR TURNBACK HAD TO USE LOCK OVERIDE TRIGGER TO RAISE GEAR, CYCLED GEAR, THEN GOT THE CONFIGURATION WARNING HORN ADVANCING THRUST REVERSERS. CONFIGURED FOR FLAPS 30LDG RETURNED TO SLC. REMOVED AND REPLACED S106 GROUND SHIFT SENSOR PER MM.