As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED ALL GEAR WOULD NOT RETRACT. CREW RETURNED TO PHX AND LANDED WITHOUT INCIDENT. CREW TAXIED OFF OF ACTIVE THEN WERE TOWED TO THE GATE. MX R & R LANDING GEAR SAFETY VALVE, 49GA IAW AIRBUS 320 MM 32-31-17-400-001. LEAK CHECK & OPS CHKS GOOD.