As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMBOUT FROM ORD, THE LEFT MAIN GEAR UNSAFE LIGHT REMAINED ON AFTER GEAR WAS RETRACTED. COCKPIT OPERATING MANUAL PROCEDURES WERE FOLLOWED AND LIGHT STAYED ON. FLIGHT WAS CONTINUED TO DESTINATION (MSP) AT REDUCED SPEED AND LANDED WITHOUT INCIDENT. MAINTENANCE REPLACED THE LEFT MAIN GEAR UPLOCK SWITCH. OPERATIONAL CHECK NORMAL. AIRCRAFT RETURNED TO SERVICE.