Rear M1 air-con compressor #1 fault while doing train prep. Unable to reset. Car was cooling.. ~~~~~ 1679 A/C 1 fault while doing train prep. Unable to reset. Car was cooling.. CE reported coolant pressure fault on car 1679 A/c 1.  1679 A/c 1-1 charged in 1 kg of 407C - Done. Tightened suction line connector coupling & function test - OK.  Chan SW/Hanafi 43957