3518 A/C 1 Inverter failure & 2518 A/C 1 ~~~~~ 3518 A/C 1 Inverter failure & 2518 A/C 1 Coolant Pressure fault. (Train Prep)  3518 FC 508 (AC1 inverter failure) Check AC1-1 & 1-2. Freon pressure of AC1-1 LP/HP: 40/110 & AC1-2 LP/HP: 40/115 psi. AC Comp and fan - ok. AC able to cut in/out. Saloon temp 23-24c. 2518 FC518 (AC1-1 HLPS) Check freon pressure LP/HP: 5/200 psi. Purged and vacuum, able to hold at -30psi. Charged 7kg of freon to LP/HP: 5/190 psi. No freon leak, AC comp and fan function - ok. Evap choked base on HP too high. Raised Ops20 to replaced AHU. Tagged AC1.  Sarma/Alan/Kamarul/Anand/Shafie 45295 BSD: To replace 2518 A/C #1-1 AHU. Tagged A/C #1.   OPS20: Replaced #2518 AHU 1 and function test ok. A/C unit able to cut in/out. Saloon temperature cooling. Notification to CSC: 2561566 Done by: Sanip, Koh, Jack (16/1/24)