As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT RETURNED TO THE FIELD WITH A LEFT MAIN GEAR DISAGREE WARNING MESSAGE. CREW LANDED WITHOUT INCIDENT. REMOVED AND REPLACED THE LT UPLOCK ACTUATOR, UPLOCK ROLLER, ADJUSTED TARGET. LANDING GEAR EXTENSION/RETRACTION FUNCTIONAL TESTED GOOD IAW AMM.