As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR TURNBACK, AFTER T/O LEFT MAIN LANDING GEAR LIGHT REMAINED RED IN THE UP POSITION CYCLE LANDING GEAR INDICATION WERE GOOD. RAISED GEAR LEFT MAIN RED LIGHT REMAINED ON. REMOVED AND REPLACED LT MLG ACTUATOR AND UPLOCK ACTUATOR PER MM.