Train EB after departing platform. TC inform no fault indication found , TC reset EB ok.y able to proceed at a speed of 6 KPH.proceed ATPM to CCK SB to disembark passengers. ~~~~~ 1686 found having abnormal brake status. Found ACUunit air leak at left side of S.V. Replaced ACU. Security & function check - OK. Brake status check - OK. Resealed STBS on both DT cars.              3685              3686 Cut-in       8.40 bar          8.30 bar Cut-out      10.20 bar         10.30 bar Air Leak     0.4 bar/5 min     0.4 bar/5 min 1686 ACU S/N : OLD : 154190. NEW : 1516109.  Redzwan/Haiqal. 20/01/2020.