1531 reported BCU FAULT. ~~~~~ 1531 reported BCU FAULT.  1531 ER D/L FC 308/330/331. Found BCP stuck. Swapped #2531 ACU to #1531 & replaced #2531 ACU. Swapped #2532 BCU to #1531 & replaced #2531 BCU. Wheel diameter setting - Done. Function check - OK. Brake cyclic check - OK. No residual pressure at COAST, all brakes able to release physically. Limited movement/depot shunting - OK.  Sarma/Alan/Lee PT/Kamarul/Anand 45156 ACU S/N : (after swapped) #1531 - 1310/139 #2531 - 1019/019 (NEW) #1531 - 1024/007 (FAULTY) BCU S/N : (after swapped) #1531 - 1816143 #2532 - 1827118 (NEW) #1631 - 1827119 (FAULTY)