As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF CREW SELECTED GEAR TO THE UP POSITION. DURING RETRACTION THE HYD CAUTION LIGHT ILLUMINATED. HYDRAULIC PUMP WOULD NOT TURN ON IN AUTO OR MANUAL. CREW USED ALTERNATE GEAR EXTENSION, DECLARED EMERGENCY AND RETURNED TO AIRPORT. MX REMOVED AND REPLACED HYDRAULIC PUMP.