TIMS showed Smoke External Alarm at rearM1 car. Staff(AMK) checked and confirmed no signs of smoke / fire / burning smell on exterior or interior of train. Rea r T431 line clear and confirmed no abnormalities. TIMS showe ~~~~~ 1537 TIMS showed Smoke External Alarm. Staff(AMK) confirmed no signs of smoke/fire/burning smell on exterior or interior of train. Rear T431 line clear and confirmed no abnormalities. CE : 1537 reset ok.  1537 FC 721 smoke external. Checked external smoke detector, no cable gland. Swapped SDR11 from 1537 to 2537. Ops 20 raised for external smoke detector c/o.  Daniel/Redzwan 45237 BSD: 1537 To changeout external smoke detector c/o.  N #1537 external smoke detector new, clean and service ok. Fix new cable gland and function test ok. To be further monitor. Done by:Sanip/Rizman Date:13/11/2023