As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ORD - CREW REPORTED ON DEPARTURE LANDING GEAR WOULD NOT RETRACT. CYCLED GEAR SEVERAL TIMES WITH SAME RESULT. EMERGENCY DECLARED FLIGHT RETURNED ORD LANDED WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. REPLACED FAULTY LANDING GEAR CONTROL LEVER MODULE. SYSTEM GROUND CHECK NORMAL OPERATION.