TIMS showed DoorObstacle Detector indication illuminated at front M1 car, 'A1' door when train doo rs opened. Fault cleared after train doors were closed. Staf f (YIS) checked and confirmed no abnormality. ~~~~~ TIMS showed Door  Obstacle Detector indi Checked Tims no door related FC observed during the reported time of fault.Checked J-rail and door guide,no FOD.Door mating strip ,satis.Pull/push resistance-5.5kgf.DCS and DLD plunger rubber checked    ,satis.Found DLS rigging out of criteria adjusted ok.Carried out door cyclic/function test,satis.Door opening/closing time,satis. Done by Joshua/Jun Hong. 08/03/22