As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE CREW REPORTED RECEIVING A LANDING GEAR DISAGREE MESSAGE ON THE EICAS AFTER TAKEOFF AND THAT THE EICAS INDICATED THAT THE LANDING GEAR WAS DOWN AND RED WITH THE HANDLE IN THE UP POSITION. MAINTENANCE INSPECTED AND REPAIRED A CORRODED PIN AT THE LANDING GEAR SOLENOID VALVE CONNECTOR. FOLLOW-ON SYSTEM CHECK PROVED A SATISFACTORY FIX AT THAT TIME.