What was found
ON FLIGHT 3843 ON APPROACH INTO MSP RECEIVED FLAPS FAIL CAUTION MESSAGE AT 0. PERFORMED TROUBLESHOOTING PER FIM REV 44 IAW AD2009-06-12 PARA (H)(6)(I) AMOC DATED DEC 7 2012 AND PA AD 27-052 J. REPLACED RIGHT BPSU IAW 27-51-10. REMOVED, CLEANED, LUBED AND RE-INSTALLED RIGHT FLAP FLEX SHAFTS IAW 27-53-10 PER MOTR GROUP. REPLACED SKEW DETECTOR UNIT IAW 27-51-15. FLAPS OPS CHECK GOOD IAW 27-54-00 CODE JAM RIGHT BPSU DIFFERENTIAL REFERENCE NRCW 31596. COMPLETED RIGGING OF FLAPS IAW CRJ 200 AMM 27-54-00, ALL CHECKS GOOD.