TC reported Rear DT B3 door slow in closing. SM(COM) checked and confirmed Rear DT B3 slow in closin g. Isolated by SM. ~~~~~ CHECK AND CONFIRMED DOOR B3 IS ISOLATED.NORMALISED DOOR AND CHECK DOOR ABLE TO CLOSE WITHOUT ABNORMALITY DOOR CLOSING SPEED OK.CHECK FOR ANY FOD OK.CHECK MATING STRIP OK.CHECK DOOR RESISTANCE OK.CLEAN J-RAIL AS PM.DOOR CYCLIC TEST CARRIED OUTTOU JUN JIE 03/01/21