Train undershoot platform by 2.5 metresin Auto mode. Proceeded in ATPM mode to the headwall. ~~~~~ TIMS did not register any fault code at undershoot timing. Checekd all car brake pressure ok. Physically checked all car brakes able to release. Found 1551 A3 parking brake unit having abnormal sound when put to B3. 1551 PB isolation cock operated,  PB manually released. STBS operated on both cabs. Train transferred for PB c/o."     /KUMAR/08.04.22