TC reported TIMS showing obstacle detected at RM1 car b4 train door. Staff(ADM) checked and confirme d RM1 car B4 train door did not open. SM(KRJ) then assisted to isolated B4 train door in closed position. ~~~~~ 1604 TC reported TIMS showing obstacle detected @B4 train door. Staff(ADM) confirmed 1604 B4 train door did not open. SM(KRJ) assisted to isolated B4 train door in closed position.  1604 B4 2 outer roller(RHS & LHS) replaced. Security checked - OK. Tested door operation for open/close & for wobbling 20x - OK. Door width gap - OK. Checked DIR - OK. Aliff/Daniel/Chan SW/Redzwan 45195