As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
GUM - FL 862 - DURING FLIGHT 'A' HYDRAULIC SYSTEM INDICATION DROPPED TO ZERO ENGINE DRIVEN HYDRAULIC PUMPS SHUT OFF. MAINTENANCE TROUBLESHOOT SYSTEM AND FOUND AIR PRESSURE REGULATOR INOP. REMOVED AND REPLACED AIR PRESSURE REGULATOR AND RESERVICED SYSTEM. PERFORMED OPERATIONAL CHECKS NORMAL. (M)