TC reported of Master Fault and Brake Fault indicators lighted up, but no fault indication on TIMS. Train was accelerating slowly out of BSD TB3. Fault self-cle ared just as the train was entering BSH SB. ~~~~~ C reported of Master Fault and Brake Fault indicators lighted up, but
no fault indication on TIMS. Train was accelerating slowly out of BSD
TB3. Fault self-cleared just as the train was entering BSH SB. (L3)

L3 'From ER, found BRER dropped during fault timing.
#3539 brakes were stuck at 0.3 bar, all others cars at 0 bar
No FC were registered.
During depot cyclic test, BCU control pressure fault triggered (FC314/331/330)
In depot, observed #3569 BCP permanently stuck at ~0.3bar when at coast. Physically checked found all brakes did not release and ACU were leaking.

Air leakage from ACU were found and all brakes did not release at #3569. Presence of residual brake pressure caused BRER unable to energise.

BRER, ABRR, PBPR, ELB2R, COR1/2 relay condition satis. Function check able to energise as required.
During function cx, #3569 BCP was able to show signs of regulation when brakes were commanded, suggesting that BCU was able to monitor and regulate the BCP.

- Replaced ACU and fault cleared. Brakes were able to release and coast at 0 bar.
- Brake cyclic test carried out and brake pressure all within criteria.
- No fault code on TIMS.
- STBS resealed

During Depot shunting observed 3569 having BCU suspension fault - FC308, 314, 315, 330, 331.
Fault self cleared and unable to duplicate in pit. Preventively changed out MPV and BCU and brake function tested ok. Brake frame found no abnormalities.

ACU:
Old SN: 1107-038
New SN: 1131-060
Notification: 2513491

BCU:
Old SN: 1834240
New SN: 1816159
Notification: 513622

MPV
Old SN: 1250415
New SN: 1050371
Notification: 3513620

Done by: Jack, Koh, Sanip, Rizman
9 Aug 2023