As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SEA- AFTER SELECTING GEAR UP, MAIN GEAR DOOR AMBER LIGHT ON AND VISUALLY CONFIRMED LIGHT GEAR DOOR FAILED TO CLOSE. PERFORMED ALTERNATE GEAR EXTENSION METHOD. LANDED OK. REMOVED AND REPLACED PSEU. OPERATIONAL CHECKS GOOD. AIRCRAFT RETURNED TO SERVICE.