1638 - TC reported brake fault.(Train pr ~~~~~ 1638 - TC reported brake fault.(Train prep)  1638 found ACU faulty. FC 308/330/331 registered. Swapped #1638 ACU with #2638 & installed new ACU at #2638. Performed cyclic test & all brake function/pressure - OK.  Alif/Sugu/Anand 45124 ACU S/N : NEW : 1549/210 (at #2638) OLD : 1508/073 (from #1638)