TC reported smoke external at RM2 car. Staff(BBT) checked and confirmed no sign of smoke. Rear T231 line clear and confirmed no abnormalities. ~~~~~ 2656 TC reported smoke external indication illuminated. Staff(BBT) checked and confirmed no sign of smoke. Rear T231 line clear and confirmed no abnormalities. CE 2656 smoke external pre-alarm unable to reset. Isolated breaker.  2656 checked & confirmed SDR11 relay in fire control panel faulty. Isolated/removed relay. Shortloop to BSD to check smoke detector.  Ashvin 44988 To check ext smoke detector and replace if necessary.     #2656 have external smoke detector alarm,remove #2 hatch cover and check smoke detector have water seepage. Replace new smoke detector and tested ok. #2656 smoke detector:- Not: 2467636 raise to CSC Done by Haslan/Asruddin. 03/03/23