What was found
AIRCRAFT NOT GROUNDED: WITH AUTOPILOTS ENGAGED WHILE FLYING ILS 18L CLT, THE AIRCRAFT TRACKED SIGNIFICANTLY LEFT OF LOCALIZER. BOTH FLIGHT DIRECTORS SHOWED A CORRECTION WAS REQUIRED BUT AUTOPILOT DID NOT CORRECT. RESET AND OP CHECKED MMR 1+2 PER AMM 34-36-31, CHECKS GOOD. RESET AND OP CHECKED FMGC 1+2 PER TSM 22-83-00, CHECKS GOOD. PERFORMED AFS TEST IAW AMM 22-96-00, CHECKS GOOD.