What was found
SPOILERS ADVISORY FAILURE OF ONE OR TWO SPOILER ACTUATORS IN AIR OR FAILURE OF ONE NOT DEACTIVATED SPOILER ACTUATOR ON GROUND. DB 27 FCM OPS (RIGHT) DB 27 FCM OPS (LEFT) DB 27 FCM OPS (CENTER)AC ARRIVED FOUND SPOILER ADVISORY. PERFORM PRIMARY FLIGHT CONTROL RIGHT HYD TEST FAILED. MSG 27-12309 CHECKED RELATED MSG 27-12309 SHOWN ON CMCF.PERFORMED GND TEST PER FIM DMC-B787-A-27-60-F1-55A-421A-A. TEST FAILED. DEFERRED PER MEL. M PROCEDURE. PERFORMED IAW DDG DDG 27-61-02. SPOILER 13 DEACTIVATED. POSITION OF DEACTIVATED SPOILER TO BE VERIFIED BEFORE EACH FLIGHT. ADDED PRESSURE TRANSDUCER, SPOILER PCU UNIT AND RESOLVER, REF MSG 27-12309 AND FIM 27-60-F1-55A-421A, ALONG WITH WIRE CHECKS SHOWS AS POSSIBLE FAULT. FAULT CONFIRMED, RE-ACTIVATED SPOILER 13 SYS TEST STILL FAILED. RT HYD PRESSURE BELOW 500 PSI IAW FIM DMC-B787-A-27-61-08-01A-520A-A. R & R SPOILER 13 PCU IAW AMM DMC-B787-A-27-61-08-01A-520A-A/720A-A DISCREPANCY HAS BEEN CORRECTED.