TC reported FM2 intermittent BCU fault when train is moving. Train performance ok. ~~~~~ 3509 TC reported intermittent BCU fault when train is moving. Train performance ok.  2509 ER D/L. Replaced ACU & swapped pressure transmitter to #1509. Function check & no air leak found - OK. Limited movement/depot shunting - OK.  Sarma/Anand 44580 #2509 ACU S/N : OLD : 1047/078 NEW : 1047/083