As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON LANDING GEAR RETRACTION AFTER TAKEOFF, LANDING GEAR REMAINED UNLOCKED. ECAM MESSAGE GENERATED AFTER APPROXIMATELY 3 MINUTES. LANDING GEAR RETRACTED. ECAM PROCEDURE HAD NOT YET BEEN ACCOMPLISHED. WHEN UNLOCKED, NOISE OF GEAR DOORS OPEN WAS HEARD. REMOVED AND REPLACED LANDING GEAR CONTROL INTERFACE UNIT (LGCIU). OPS CHECKED GOOD.