As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: AN EMERGENCY WAS DECLARED DUE TO: LANDING GEAR WOULD NOT RETRACT AFTER TAKEOFF. AIRCRAFT AIR INTERRUPTED BACK TO AND LANDED SAFELY AT ORD. ACCOMPLISHED MAIN LANDING GEAR OPERATIONAL TEST, PER AMM 32-32-00. MAIN GEAR MANUAL EXTENSION SYSTEM TEST-AIRPLANE ON JACKS, PER AMM 32-34-00. OPERATIONAL CHECK NORMAL NO DEFACTS NOTED AND ACCMOPLISHED WORKCARDS 08L00005010, 08L00007004 AND 08L00005013, NO FAULT FOUND.