As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DTW - FLT 3312 - DURING APPROACH, THE 'GEAR DOOR POSITION' WARNING LIGHT ILLUMINATED. THE LIGHT FLICKERED, THEN EXTINGUISHED DURING ROLL-OUT. AFTER EXTENSIVE TROUBLESHOOTING AND INSPECTION, MAINTENANCE PERSONNEL WERE UNABLE TO DUPLICATE THE DISCREPANCY. (X)