1552 TC reported during train prep havin ~~~~~ 1552 TC reported during train prep having BCU fault.  1552 ER D/L & found FC 308/330/331. Replaced ACU & function test - OK. Brake cyclic test, limited movement & depot shunting - OK. No fault re-occur. #1552 ACU S/N : OLD : 1037/048 NEW : 1310/145  Sarma/Anand 44227