Train encountered stuck brake at rear M1car while departing from TAP NB. TC operated STBS and proce eded in ATPMto disembark pax at BDL NB. ~~~~~ #1603, FC 330, 331, 308, 314. Hunting and air leak from ACU exhaust port. Replaced and brake function test ok. STBS resealed back. ACU- Old s/n: 1429-010  New s/n: 1516-096. Not: 2134186 raise to RSW.    Done by Faiz/Sanip. 23/02/20.