TC reported DIR intermittent lighted updeparting station. Request staff(TAP) to sweep train and fou nd no abnormalities of train door. TC reported fault occur o nly when departing NOV station. ~~~~~ To replace 3519 B1 door manifold.  3519 B1 door manifold replaced. Function test - OK. Performed door gauge test (10mm/20mm) - OK. Open/close door timing checked within criteria.  Farid/Haiqal 44365 #3519 B1 Door Manifold S/N : OLD : 10273 NEW : 10427 3519 TC reported DIR intermittent lighted up departing station. Request staff(TAP) to sweep train and found no abnormalities of train door. TC reported fault occur only when departing NOV station. CE check N . Depot to check (OE).  3519 B1 door manifold v/v air pipe adaptor found leaking. OPS 20 raised to replaced manifold.  Chan GF 44365