As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT 301,AIR TURNBACK. BLUE SIDE LOW LEVEL WARNING LIGHT AND CCAS BLUE HYDRAULIC CAUTION IN FLIGHT. AIRCRAFT WAS RETURNED TO HNL. EMERGENCY WAS DECLARED. LANDED WITHOUT FURTHER INCIDENT. MAINTENANCE REPLACED THE BLUE HYDRAULIC PUMP, HYDRAULIC HOSE AND GREEN HYDRAULIC SYSTEM PRESSURE FILTER. OPS AND LEAK CHECKS GOOD. AIRCRAFT RETURNED TO SERVICE.