What was found
AMS CTRL FAIL CAUTION MESSAGE APPEARED AT APPROXIMATELY FL230-240 DURING DESCENT ON ARRIVAL. (FLIGHT 6256 - FILED CLOSED) INTERROGATED CMC AND FOUND FAULT CODE 21000100. TROUBLESHOT PER ERJ-175 FIM 21-00-00-810-808-A. REMOVED AND REPLACED AMS CTRL MICRO MOD ON SPDA 2 SLOT 25 IN REFERENCE TO ERJ-175 AMM 21-00-01. CHECKED AND VERIFIED BOTH AMS CTRL MICRO MODS HAVE SAME SOFTWARE IN REFERENCE TO ERJ-175 AMM 21-00-00-910-802-A. MSGS CLEARED. A/C OK FOR CONT SVC.