As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: LANDING GEAR DOORS NOT CLOSED. ON APPROACH AFTER LOWERING THE GEAR THE LEFT MAIN GEAR DOOR FAILED TO CLOSE. MAINTENANCE FOUND BOLT ON UPLOCK PROXIMITY SWITCH LOOSE AND TIGHTENED BOLT PER AMM 20-21-11. A SATISFACTORY OPERATIONAL CHECK WAS ACCOMPLISHED.