TC reported rear DT "A2" door not provenclosed. TC recycle twice for train doors proven closed. ~~~~~ 3542 TC reported A2 door not proven closed. TC recycle twice for train doors proven closed. CE 3542 all doors proven open and closed. Depot 3542 train door operational check.  3542 A2 Door wobbiling during opening. Found door roller outer side damaged. Replaced new roller & security checked - OK. Function test door open/close 20 times - OK. Conduct door gauge test (20mm)- OK. Checked door mechanism - OK. No abnormalities found. Fault cleared. Chan/Aliff/Redzwan 45187