In depot found EMU 636 unable to aux on. ~~~~~ To further check EMU363 BCB trip Check line #6606 to grd and from #3636 MPUCB found shorted 280ohm.Further check #6606 from junction M2-#1,M1-#2,#1,DT-#2,#1 and to grd ok.Found B106/6606 Dd diode shorted.Replace diode and measure ok no shorted to grd.Function test Aux on ok.BCB to tripped.Battery voltage ok.Monitor ok no occurance of fault. Done by Saini/Kumar. 04/07/24 In depot found EMU 636 unable to aux on.  NO FC observed in tims. Found EMU636 3 car BCB was trip, try normalise train will aux on few sec and BCB will trip again and Aux off. Further check battery charger, Aps equipment, battery bank output 95vdc ok, battery fuse ok and no sign or burn mark. saloon side BCB no observed any abnormal or burning smell. Uncoupler and try normalise BCB, but no available, try flat battery start up at EMU636 ok. Aux on and normalise BCB was no trip, but BATK still open condition, Aux off/Aux on BATK ablr to energize and hold. Once train Aux off, BCB EMU636 will automatically trip. Ops20 to follow further check. Done by:Jack/Sanip/Koh Date:02/07/2024