TC reported TIMS showed both External and Internal Smoke Detectors were isolated in car 3502. ~~~~~ TC reported TIMS showed both External an     Check the above FC 721 on #3502 only.Replaced external smoke detector done.Security check and normalise back for testing ok. #3502-Smoke detector:- Not: 2466681 raise to CSC. Done by Saini/Haslan. 02/03/23