3631 BCP 0.19 remain at coast ,found dur ~~~~~ 3631 BCP 0.19 remain at coast ,found during DT cx. 3631 TC reported train come to a stop momentarily departing station with stuck brake fault at Front DT car. Fault self cleared and train continue in AM to next station. Stock change arranged at AMK MT.  3631 ER & Fault Trace D/L & found FC 308/330/331/314/312. Found BCP spiked. Found ACU AC SV failure & replaced ACU - Done. Function check brake pressure - OK. BCP 1 & 2 no residual pressure, '0' at COAST. All brakes released at COAST. No air leak. Limited movement/depot shunting - OK. 3631 ACU S/N :   OLD               NEW ACU  :         1473/010          1508/036 (MOD 3) RF   :         1739/726          1740/789 (MOD 3) RC   :         1739/736          1740/831 (MOD 4) AF   :         1739/152          1847/912 (MOD 4) AC   :         1739/077          1847/963 (MOD 4) EM   :         1739/723          1902/017 (MOD 4)               (All MOD 3)  Sarma 44051