As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RDG-PIT FLIGHT#3923. CREW SELECTED GEAR DOWN, SAW YELLOW IN-TRANSIT LIGHTS AND RED GEAR HANDLE LIGHTS ILLUMINATE. GEAR DID NOT EXTEND. ALTERNATE GEAR EXTENSION PERFORMED, AND FLIGHT LANDED WITHOUT INCIDENT. MAINTENANCE REPLACED LANDING GEAR SELECTOR VALVE IN ACCORDANCE WITH DASH 8 MAINTENANCE MANUAL 32-30-41. OPERATIONAL AND LEAK CHECK GOOD. AIRCRAFT RETURNED TO SERVICE.