TC reported Front M1 car brake fault. TCoperated STBS an proceeded in ATPM mode to the next station . ~~~~~ Downloaded ER and fault trace on PTU006. #1677 when B1 to coast, BCP = 0.7 bar, air leaking from solenoid course exhaust. #1677 ACU AF and AC s/v mod 3. Replaced ACU and carried out brakes cyclic/function test ok. #1677-ACU: Old s/n: 1541-185  New s/n: 1450-061. Not: 2200352 raised to RSW. Done by Koh/Joshua. 16/09/20.