Fujitsu AS G07LUCA Series Service Instruction page 104

2-4 TROUBLE SHOOTING WITH ERROR CODE
Trouble shooting 45
INDOOR UNIT Error Method:
External Communication Error
(Communication Error of between
Indoor Unit to Wireless LAN adapter)
Detective Actuators:
Wireless LAN adapter PCB
Controller PCB
Forecast of Cause:
1. Connection between A/C and Wireless LAN adapter failure
2. Wireless LAN adapter PCB failure
3. Controller PCB failure
Check Point 1 : Check the connection
Check any loose or removed connection of between the Wireless LAN adapter PCB and Controller PCB
>If there is abnormal condition, correct it.
Check the connection condition on the Controller PCB
>If there is loose connector, open cable or miswiring, correct it.
OK
Check Point 2 : Replace wireless LAN adapter
If Check Point 1 do not improve the symptom, replace Wireless LAN adapter and
Please cancel the air conditioner of the registration on the Mobile App.
After the replace adapter, Please perform the pairing on the app.
>>Air conditioning de-registration method, refer to page "02 - 65"
>>Pairing method, refer to page "02 - 66"
OK
Check Point 3 : Replace Controller PCB
If Check Point 2 do not improve the symptom, replace controller PCB.
Indicate of Display:
Indoor Unit :
Operation lamp: 1 times Flash,
Timer lamp : 8 times Flash
ERROR CODE : [ 18 ]
Detective details:
After receiving a signal from the wireless LAN adapter,
the same a signal has not been received for 15sec.
02-59
(For WIRELESS LAN ADAPTER)
Wireless LAN adapter :
LED 1 (Green)
LED 2 (Orange) : ON
NG
Controller PCB
: Flashing Fast