Train encountered BCU fault at rear M2 car but fault self cleared when departing station. ~~~~~ 2569 encountered BCU fault but fault self cleared when departing station.  2569 found having intermittent BCU fault (FC 330/331). Replaced ACU unit MOD 4 - Done. Security/function test - OK. Brake pressure check - OK. 2569 ACU S/N : OLD : 1042-068 NEW : 1340-140  Redzwan/Hanafi    44021