As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING THE TEST OF THE RUDDER PCU'S THE TEST FAILED USING THE LT HYDRAULIC SYSTEM. THE SYSTEM TESTED OK USING THE RT AND CENTER HYDRAULIC SYSTEMS. USING THE LT SYSTEM ALONE THE RUDDER HAD NO MOVEMENT TO THE LEFT AND SLIGHT MOVEMENT TO THE RIGHT AND WOULD NOT RETURN TO CENTER. SUPPLEMENTAL DATA UPDATE, NO DISCREPANCIES FOUND WITH LEFT POWER CONTROL UNIT FOR THE RUDDER. FAULT WAS WITH THE CENTER PCU. REPLACED PCU.