Train Prep:561/562 BCU fault, ~~~~~ Train Prep:561/562 BCU fault,     #1562/#2562 brake cyclic test ACU #1562 no abnormalities.#2562 ACU exhaust port heavy purge due to plastic tube not insert properly.Remove ACU and re-install the plastic tube ok.#1562 no residual pressure at silencer.#1562 swap ACU to #1562.Function test #1562/#2562 brake cyclic,ACU no abnormalities.BCP within criteria.To be monitor at mainline. Done by Zulq/Asruddin. 21/02/22