As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CRUISE FLIGHT, THE NR 2 HYDRAULIC SERVO SYSTEM WARNING CAUTION LIGHT ILLUMINATED. DECLARED EMERGENCY AND RETURNED TO DEPARTURE. REPLACED THE NR 2 SERVO RELAY AND AS A PRECAUTION, REPLACED THE NR 2 HYDRAULIC MODULE PRESSURE SWITCH.