As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON CLIMB OUT, CREW RECEIVED A LT MAIN LANDING GEAR UNSAFE LIGHT AFTER GEAR RETRACTION. CREW RECYCLED GEAR WITH SAME RESULTS. FLIGHT RETURNED TO FIELD AT PI AND LANDED WITHOUT FURTHER INCIDENT. NO EMERGENCY WAS DECLARED. MAINTENANCE REMOVED AND REPLACED THE LEFT MAIN LANDING GEAR UPLOCK SENSOR IAW MM. SWUNG GEAR SEVERAL TIMES. OPERATIONAL CHECK AND INDICATION CHECK TEST GOOD.