As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED LOST YELLOW SYSTEM QTY AND PRESSURE IN FLIGHT. UPON ARRIVAL FOUND HYD FLUID COMING FROM PTU MANIFOLD CHECK VALVE 3094GM. O-RING FOUND DAMAGED. REPLACED O-RING, SERVICED YELLOW HYD. RAN BOTH ELECT YELLOW AND RAN NR 2 ENG YELLOW PUMP. NO LEAKS AND ALL OPS NORMAL. CHECKED YELLOW POPPETS ON FILTERS, OK.