TIMS showed Smoke Internal alarm at Front M1 car. Staff (KAL) checked and feedback no sign of heat a nd smoke. Train reformed to withdraw at PSR, return to CHD. Rear T334 was used. TIMS showed Smoke Internal at FM1 car. S ~~~~~ * ,N * Cleaned 1562 both air return smoke detector with compressed air. Function check ok. For monitoring, swapped 1562 FCP (011) with 2561 (174). Function check ok. DONE BY: ZAIDI/RAWI 15.07.2023