3521 - BCU COMM FAULT. TO CHECK & RECTIF ~~~~~ 3521 - BCU COMM FAULT.  3521 FC 307, 301. Depot shunting, checked no fault.    Swapped BCU from #3521 to #1521. Brake cycle - OK. s/n after swap: #3521: 1809060 #1521: 1812096  Sugu/Anand/Lee PT/Kamarul 45265 OE to request to replace 1521 BCU.  1521 replace BCU and function test, brake cyclic test are ok.                                                              Serial no:1812-096, new:2007-263, notification 2548884 Done by Yusof/Haikel/Morgan 45266