As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) AFTER TAKEOFF, WHEN SELECTING THE LANDING GEAR UP, THE NOSE DOOR OPEN WARNING APPEARED. MAINTENANCE REPLACED THE NOSE GEAR DOOR SELECTOR VALVE (P/N:55540-5, S/N OFF: 1131/S/N ON: 1197) AND THE PROX. SENSOR P/N: 8-648-07 & P/N: 8-648-08.