SBW staff feedback train doors externallight at front DT and front M1 cars did not light up when tr ain doors were opened. ~~~~~ SBW staff feedback train doors external light at front DT(3520) and front M1(1520) cars did not light up when train doors were opened. CE checked & found 3520 n 1520 both A/S train external light not working.   3520 n 1520 both A/S train external light not working. Replaced both exterior light & function checked -OK. Alan/Leept/Kamarul 44962