TIMS showed BCU fault at car 3633.Trainintermittenly come to gradual stop. TC operated STBS to proc eed. Pax were detrained at RFP WB ~~~~~ 3634 & 2634 TIMS showed BCU fault. L3 Train intermittenly come to gradual stop. TC operated STBS to proceed. Pax were detrained at RFP WB - L3 3633 STBS seal resealed. 633/634 at coast, all brake release except 3633. 3633 BCU replaced. Retest brake operation - All able to release & applied at coast/brake. 3633 brake shoe condition - OK. Checked SAP: wheel diameter 835mm 3633 BCU: Old: 1431-033 New: 1847413 Chan SW/Hanafi 44617  3634 No.4 & 2634 No.3 transducer replaced. TEsted operation - OK. Alan/Shafie/Lee PT 44617  3634 No.4 & 2634 No.3 transducer replaced. Tested operation - OK. Alan/Shafie/Lee PT 44617