As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED A GEAR DISAGREE WARNING WHEN SELECTING THE LANDING GEAR DOWN WHILE ON APPROACH TO PHL. NOSE GEAR WENT DOWN, BUT MAIN GEAR REMAINED UP. CREW MANUALLY RELEASED AND PUT DOWN THE GEAR AND LANDED IN PHL WITHOUT FURTHER INCIDENT. MAINTENANCE TROUBLESHOT THE AIRCRAFT, REMOVED AND REPLACED THE MAIN LANDING GEAR SELECTOR VALVE AND PERFORMED CHECKS USING THE AIRCRAFT MAINTENANCE MANUAL. AIRCRAFT WAS RELEASED FOR SERVICE.