EMU 611/612 # 2611 BCU Com. fault. ~~~~~ To follow up.  2611 BCU swapped to #1611 & fault transfer. Replaced BCU at #1611. Fault cleared. Brake pressure check & physically checked all brakes fully released when at COAST.  Alan/Lee PT/Shafie 44326 #1611 BCU S/N : OLD : 1503112 NEW : 1830132 During PM check brake pressure and physically brakes are fully releaseed when at coast are ok. Checked by Team 6. 12/05/21 / 2611 BCU Com. fault.  2611 found FC 308 (BCU Fault) & 301/307 (BCU Comms Fault). Physically check #2611 brakes fully applied when train at COAST. Replaced BCU & fault persisted. OPS 20 raised to follow-up.  Chan SW/Hanafi 44326 #2611 BCU S/N : OLD : 15-17-177 NEW : 1503112