As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CRUISE, THE LT HYD STATUS QTY ILLUMINATED, RF STATUS MESSAGE NEXT TO L HYD QUANTITY. 3000 PSI MAINTAINED UNTIL L HYD PUMPS TURNED OFF. FLIGHT DECLARED AN EMERGENCY AND RETURNED TO ORD WITHOUT FURTHER INCIDENT. FOUND #6 SPOILER ACTUATOR FILTER CAP O-RING BLOWN OUT. REMOVED AND REPLACED O-RING AND FILTER IAW CMM 27-61-02. THE AIRCRAFT WAS GROUNDED.