As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) LANDING GEAR FAILED TO EXTEND ON APPROACH, LANDING GEAR HANDLE MOVED BUT HYDRAULIC VALVE LEVER DID NOT MOVE. LANDING GEAR EXTENDED WHEN HYDRAULIC VALVE WAS OPERATED IN THE MANUAL MODE. MAINTENANCE INVESTIGATION REVEALED THE ROLL PIN OF THE LANDING GEAR CONTROL ASSEMBLY WAS NOT CORRECTLY INSTALLED WHICH CAUSED IT TO SHEAR.