TIMS showed BCU unit healthy fault and intermittent brake fault upon approaching every headwall of a ll station. Train performance - ok ~~~~~ 3539 BCU unhealthy. Fault trace shows FC 324 (Speed probe 1 fault), FC 322 (BCU WSP Timer 1 activated). Checked and found #3539 speed probe 1 OL.  Kana. 11/03/2021.  3539 Tacho 1 replaced. Limited movement/depot shunting & found no BCU, brake or W/S/S fault. #3539 Tacho 1 S/N : OLD : 1032132. NEW : 935019.  Chan SW/Hanafi. 12/03/2021.