As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON APPROACH INTO YYZ WHEN FLAPS 30 WAS SELECTED NEEDLES REMAINED IN FLAPS 25 POSITION BAND. "TO LOW FLAPS" AURAL WARNING SOUNDED. MISSED APPROACH WAS EXECUTED. RECTIFICATION TROUBLESHOOTING CARRIED OUT AS PER MM 27-51-000-5. UNABLE TO FAULT. SUSPECT FROZEN DRUM AND CABLES. HEAT APPLIED AND LUBED DRUM AND CABLES GROUND CHECKED SERVICEABLE.