TC reported smoke external rear m2 car.Rear train T257 no abnormality. Staff (NOV) confirmed no abn ormality interior and exterior. TC reported smoke external r ear m2 car. Rear train T257 no abnormality. Staff (NOV) conf ~~~~~ TC reported smoke external rear m2 car. #2519 checked found ext. FSD water ingress. Replaced new unit with plaseal and function tested satis. Notification to CSC: 2517649 Done by Sanip, Firas, Imran. 23/8/2023.