As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DTW - FLT 3051 - DURING APPROACH, LANDING GEAR WOULD NOT EXTEND. THE CREW RECYCLED THE GEAR. THE PROBLEM REMAINED. THE CREW USED THE ALTERNATE EXTENSION SYSTEM AND THE GEAR LOCKED DOWN. THE FLIGHT CONTINUED TO DTW WITHOUT INCIDENT. MAINTENANCE PERSONNEL REPLACED THE LANDING GEAR SELECTOR VALVE. ALL SYSTEMS OPERATED SATISFACTORILY. (X)