What was found
FLIGHT 5277 - ON APPROACH TO BWI, SELECTED FLAPS FROM 20 TO 30 DEGREES, RECEIVED FLAP FAIL CAUTION MESSAGE. APPLIED QRH AND LANDED AT 20 DEGREE FLAP WITHOUT INCIDENT. COMPLIED WITH AD 2006-12-21 FLAP CAUTION MESSAGE FIRST EVENT MAINTENANCE ACTION PARAGRAPH (G) 1, 2, 3 (A, B, C). FLAP SYSTEM WAS RESET WITH NO FURTHER MESSAGES.