What was found
ON FLIGHT 3743/ (YYZ- DTW) FLAPS FAIL AT 20 DEGREES ON APPROACH INTO DTW WHILE PASSING 20 WITH A COMMAND OF 40. AIRCRAFT LANDED SAFELY. PERFORMED TROUBLESHOOTING PER BOMBARDIER FIM REV 44 IAW AD 2009-06-12 PARAGRAPH (H) (6)(I) AMOC DATED DECEMBER 07,2012, AND PA AD27-052J. DOCUMENT WORK PERFORMED. SELF-TEST OF THE FLAP CONTROL LEVER TESTED GOOD PER AMM 27-51-01. OPERATIONS CHECK OF FLAPS GOOD PER AMM 27-54-00-710-801. FLAP CODES: UNSPECIFIED; 19 C1.