Train doors at car 3648 were not provenclosed. TC recycled the train doors a few times but to no av ail. DIRBS was operated for train to proceed in ATPM mode ba ck to BSD. ~~~~~ Train doors at car 3648 were not proven     DIRBS was operated on #3647,#3648 B4 door fault code 993,994 ,996.Found DLS red mark fail.DLD found intermittent stuck.Replaced new D mark-visible ok.Push/pull before 9kg.Service clean guide rail,J rail found no FOD.Push/Pull after 7kg.Mating before 65.6mm,adjusted to 63.7mm.Door static test timing ok.Door cyclic test few time ok.DIRBS reseal. #3648-B4 door DLD KSF B train- New s/n: C151-BDL-162126 Old s/n: C151-BDL-162111 Not: 2387071 raise. Done by Zulq/Saini/Haslan.  01/06/22