What was found
SLATS DRIVE CAUTION PRIMARY AND SECONDARY SLAT DRIVES HAVE FAILED TO OPERATE, OR HAV E BEEN SHUT DOWN BECAUSE OF AN ASYMMETRY, SKEW/LOSS, DISAGREE, OR UNCOMMANDED MOTION. DB 27 FCM OPS (RT) DB 27 FCM OPS (LT) DB 27 FCM OPS (CENT). MESSAGE APPEARED AN HOUR INTO FLT. SLATS DID NOT DEPLOY FOR LANDING & ARE LOCKED. INTERREGATED CMCF & FOUND SLAT DRIVE FAULT WITH MAINTENANCE MESSAGE 27-22463. REPLACED C2 ACE FOUND MAINT MSG 27-22463. TS REF FIM 27-80-F1-39A-421A, REPLACED C2 ACE REF 27-02-17-00A-520A. ACCOMP ACE LRU REPLACEMENT TEST. NO FAULTS. OPS FLAPS & SLATS, NO ISSUES OK FOR SERVICE.