Samsung IDH4400A Service Manual page 39

Trouble Shooting
EC08 : When the trouble is found on the part related to the wireless receiving board of
the indoor unit.
Check point :
- Defect of wireless remote controller PCB
- Defect of wireless remote controller receiving board PCB
- Indoor unit PCB defect
Mis-insertion of CN9?
Wire shorted?
LED direct/reverse direction check?
Check no.1 and no.2 pin of CN9:DC +5V?
Check pin no.1 of CN9 while pressing
SW91 : DC 0V?
Replace after check of indoor unit
main PCB
4-12
NO
NO
NO
YES
YES
YES
Insert correctly
YES
YES
NO
NO
Replace the wireless receiving board
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