As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER STARTING ENGINES AND TURNING HYDRAULICS ON, THERE WAS NO PRESSURE. INSTALLED SERVICEABLE HYDRAULIC POWER PACK ASSY IAW DO228 AMM 29-10-19. FUNCTIONAL AND LEAK CHECKED GOOD. (SUSPECT HYDRAULIC PUMP FAILED INTERNALLY. HYDRAULIC PUMP MOTOR OPS CHECK GOOD, HYDRAULIC PUMP SHAFT IS NOT SHEARED AND PUMP ROTATES FREELY.