TC reported rear M2 car intermittent brake fault from NOV1 to TAP1. Train performance ok. ~~~~~ 2555 TC reported intermittent brake fault from NOV1 to TAP1. Train performance ok.  2555 ER D/L & found FC 330/308/331. Swapped #2555 ACU to #1555. Replaced #2555 BCU. Brake cyclic test - OK.  Kana/Nelson 44332 #2555 BCU S/N : OLD : 2007257    NEW : 1825079 ACU Swap : S/N : 1042/075 (Now at #1555) S/N : 1042/077 (Now at #2555)