As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) IN CRUISE AFTER APPROXIMATELY 1.5 HOURS IN FLIGHT, YELLOW HYDRAULIC FLUID LEVEL WENT LOW LEVEL. AIRCRAFT DIVERTED AND LANDED IN WINNIPEG. POWER TRANSFER UNIT (PTU) REPLACED. OPERATION CHECKED SERVICEABLE AS PER AIRCRAFT MAINTENANCE MANUAL REFERENCE 29-23-41-870-051.