As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
YELLOW SYSTEM LOW PRESSURE FAULT RESULTED IN THE AIRCRAFT DIVERTED. AN EMERGENCY WAS DECLARED AND THE AIRCRAFT LANDED WITHOUT FURTHER INCIDENT. REPLACED DAMAGED O-RING ON PTU MODULE FITTING AND ACCOMPISHED A SATISFACTORY LEAK CHECK IAW AMM 20-29-00 AND AMM 29-12-00. AIRCRAFT WAS GROUNDED