As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 3421 - DURING APPROACH TO DTW, THE RT MAIN GEAR DOWN AND LOCKED GREEN LIGHT DID NOT ILLUMINATE WHEN GEAR SELECTED DOWN. THE CREW RECYCLED THE GEAR TWICE AND RECEIVED A GREEN LIGHT. THE AIRCRAFT CONTINUED TO DTW AND LANDED WITHOUT INCIDENT. MAINTENANCE PERSONNEL REPLACED THE RT MLG UPLOCK ACTUATOR. ALL SYSTEMS OPERATED SATISFACTORILY. (X)