Fujitsu AU G18LVLB Series Service Instruction page 49

Trouble shooting 5
INDOOR UNIT Error Method:
External communication error
Detective Actuators:
External communication error
Forecast of Cause :
1. Connection failure
Check Point 1 : Check the connection
Check any loose or removed connection of between the controller PCB to the external I/OPCB and Wi-fi adapter
>>If there is an abnormal condition, correct it by refer to installation manual or
the technical manual.
Check the condition condtion on the external I/O PCB, Wi-fi adapter and the controller PCB
(If there is loose connector, open cable or mis-wiring)
OK OK
Check Point 2: Replace external I/O PCB, Wi-fi adapter
If Check Point 1 do not improve the symptom, change External I/O PCB and Wi-fi adapter.
OK OK
Check Point 3: Replace Controller PCB
If Check Point 2 do not improve the symptom, change Controller PCB.
Indicate or Display:
Indoor Unit : Operation lamp: 1 time Flash,
ERROR CODE : [E : 18]
Detective details:
After receiving a signal from the external I/O PCB,
the same a signal has not been received for 15sec
2.External I/O PCB, Wi-fi adapter failure
Timer lamp: 8 time Flash
Economy lamp : Continuous flash.
3.Controller PCB failure
02-10
Outdoor unit :
PUMP LOW
POWER
DOWN NOISE
ERROR
(L1) (L2) (L3) (L4)
MODE
5 15
2
PEAK
CUT
(L5) (L6)