Samsung APH289SEF - Troubleshooting: No Power

Samsung Electronics26
1. Causes of Failure
1) Power voltage out of the motion boundary or poor power cord contact.
2) Main PCB fuse cut or poor PCB.
3) Poor panel PCB, poor assembly of tact switch, poor LED display.
2. Inspection Items
1) Power voltage? (AC198V ~ AC264V)
2) Power cord contact?
3) Power fuse(F701) and PCB fuse(F101)?
4) Output voltage of U303(KA7805) (DC4.5V ~ DC5.5V)?
5) Connection harness between Main PCB and panel PCB?
3. Inspection Procedure
Turn power off and on in 5 seconds.
Press OPER key. LED Lights
on and shutter open?
Check U303 output voltage, 5V?
Check voltage of CN901 #1 ↔ 5 of panel
PCB, 12V? If yes, then Inspect and
exchange panel PCB(Poor panel PCB).
Power voltage normal (Fuse : AC ↔ AC)?
AC198V ~ AC264V
Good set operation
Check wire between indoor unit &
outdoor unit. Exchange wire.
Inspect and exchange Main PCB.
No
Yes
Yes
Yes
No
No
5-3 Troubleshooting by Phenomena
5-3-1 When it is not Power on. (When it is not Displayed.)