As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED, RECEIVED A LANDING GEAR AIR/GROUND FAIL MESSAGE ON TAKEOFF AFTER LANDING GEAR RETRACTION. THE CREW RETURNED TO FIELD AND LANDED WITHOUT INCIDENT. MAINTENANCE REPLACED THE NOSE LANDING GEAR PROXIMITY SWITCH AND THE WEIGHT ON WHEEL HARNESS.