Train encountered brake fault at rear M2car. TC operated STBS and proceeded in ATPM. SM(WDL) assist ed to isolated rear M2 car BIC. ~~~~~ L3 2614 ER D/L & found FC 308/314/328/329/330/331. Replaced 2614 ACU & ACU transmitter. Pneumatic Test & brake pressure test - OK. 2614 ACU S/N : OLD : 1439-031. NEW : 1508-076.  Goh AT/Chan GF. 24/03/2020.