As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) DURING APPROACH, ACFT EXPERIENCED THE GEAR DISAGREE MESSAGE DURING EXTENSION. IT WAS NOTED THAT THE NLG DID NOT EXTEND. NLG ALTERNATE EXTENSION WAS USED AND THE ACFT LANDED WITHOUT INCIDENT. MECHANICS TROUBLESHOT THE ACFT AND REPLACED THE NLG SELECTOR VALVE, LANDING GEAR CONTROL PANEL AND VERIFIED NR 3 HYDRAULIC SERVICING.