As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER COMPLETION OF ENGINE TREND MONITORING, HYD CAUTION LIGHT ILLUMINATED ON CENTRAL WARNING PANEL. BOTH MAIN AND EMERGENCY ACCUMULATOR PRESSURE LOW. AUTO FUNCTION DID NOT WORK. EMERGENCY DECLARED. ACFT RETURNED TO AIRPORT WITH NO FURTHER INCIDENT. R & R EMERGENCY ACCUMULATOR IAW AMM 29-10-20-04 AND ENGINEERING CHANGE ORDER. OPS AND LEAK CHECK GOOD.