What was found
(CAN) FLAP FAIL CAUTION MESSAGE DISPLAY ON EICAS (ENGINE INDICATIONS AND CREW AL ERT SYSTEM), QRH PERFORM WITH A NORMAL LANDING. RESET DONE AND FOUND SERVICEABLE BUT DEFECT RE-OCCURRED. FECU (FLAP ELECTRONIC CONTROL UNIT) CHANGED AS A PREVENTIVE MEASURE WITHOUT ANY SUCCESS, THE DEFECT RE-OCCURRED, AFTER FURTHER INVESTIGATION, MAINTENANCE FOUND TO BE THE PDU (POWER DRIVE UNIT) TO BE AT FAULT. REPLACED POWER DRIVE UNIT AND ALSO ADJUSTED #6 & 7 POTENTIOMETERS FECU AND PDU WIRING CHECK (NIL FAULT DETECTED). FLAP RIGGED AND OPERATIONAL CHECK CARRIED OUT...