TC reported brake fault with no DMI indication. Train come to a stop in Auto mode when approaching B GB NB. TC proceed ATPM to BGB NB. Fault self-cleared. Train able to proceed in Auto mode when departing BGB NB. ~~~~~ 3629 TC reported brake fault with no DMI indication. Train come to a stop in Auto mode when approaching BGB NB. TC proceed ATPM to BGB NB. Fault self-cleared. Train able to proceed in Auto mode when departing BGB NB.  3629 ER D/L, found FC 309 & abnormal braking pressure. 3629 BCU replaced. Security/function check - OK.  Alan/Lee PT/Shafie 44532    #3629 BCU S/N : OLD : 1509-158 NEW : 1509-162