TC reported air-con fault. Unable to reset. Staff(CCK) checked and confirmed that car 3648 set #2 ai r-con faulty. Reset - ok. Car was cooling. TC reported air-c on fault. Unable to reset. Staff(CCK) checked and confirmed ~~~~~ BSD: Ops-20 raised to check 1648 Evap Unit for leaks. 1648 TC reported air-con fault Unable to reset. Staff(CCK) confirmed 3648 A/C 2 faulty. Reset - ok. Car was cooling. 3647 A/C #2 fault. CE checked : 1)3647 both AC running with cooling. Temp 23.6*C 2)3648 A/C #2 unable to cut-In. Temp 28.0*C. A/C Warm. 3)1648 A/C #1 compressor & coolent pressure fault.  1648 FC 618, 518 ( HLPS1 Operation ). Measure freon at #1648 unit 1-1 and 2-1 freon pressure low HP 10psi, HP 60psi. Discharge & vacuum. Charge freon both unit to LP 40psi, HP 110psi. Monitor for 2 hours, no leak detected at CCU. Ops-20 raised to check Evap Unit. #3647 checked/found no fault indication & LP 40psi HP 110psi. #3648 A/c 2 refer to M/O 11840092.  Chan sw/Aliff/Daniel/Redzwan 45258