Train departed UPD TB2 with front M1 brake fault. TC feedback train slow pick up. TC updated fault s elf cleared approaching JURMT. Train will be withdrawn back to UPD. ~~~~~ 1668 ER D/L & found FC 330/331/312/314. Replaced ACU on 1668 - Done. Brake pressure test & limited movement - OK. 1668 ACU S/N : OLD : 1442-033. NEW : 1549-220.  Selvan/Lee PT/Anand. 03/03/2020.