1558 - BCU FAULT (TRAIN PREP) ~~~~~ 1558 - BCU FAULT (TRAIN PREP).  1558 ER D/L FC 308/330/331. ER showed BCP when COAST to EM, maintained at stuck brake condition. Swapped ACU from #2558 to #1558 & replaced new ACU at #2558. Brake cyclic check - OK. Brakes able to release at COAST. Brake pressure check within criteria. No air leak at ACU. Limited movement/depot shunting - OK.  Sarma/Alan/Kamarul/Shafie 45152 ACU S/N : (after swapped) #1558 : 1301/120 #2558 : 1024/033 (NEW) #1558 : 1302/132 (faulty)