Pax feedback to staff(DBG) that whole train was warm. TC confirmed air-con fault indicated. Unable t o reset. Staff(MRB) checked and confirmed that car 3684 set #1 air-con faulty. Reset - ok. Car was warm. ~~~~~ Pax feedback to staff(DBG) that whole tr     Check Tims AC page found #3684 a/c 1 temp 60degC.Replace MCU function test ok,Temp a/c 1 was 23degC and cooling ok.Monitor no fault recure. MCU:- Old s/n: 841953 New s/n: 841803 Not: 2431438 raise.    Done by Rizman  31/10/22