As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) THE AIR CONDITIONER DRIVE QUILL SHAFT WAS FOUND SHEARED DURING ROUTINE INSPECTION OF THE SHAFT. IT WAS DUE TO A DRIVE PULLEY BEARING SEIZURE. THE 2 BEARINGS THAT SUPPORT THE DRIVE PULLEY ARE ON CONDITION. 1 BEARING FAILED BEFORE INSPECTION WOULD HAVE FOUND IT TO BE WORN.