Fujitsu AU G18LVLB Series Service Instruction page 64

Trouble shooting 20
INDOOR UNIT Error Method:
Indoor Unit Fan Motor1 Error
Detective Actuators:
Indoor unit Controller PCB
Indoor unit fan motor
Forecast of Cause:
1. Fan rotation failure
4. Controller PCB failure 5. Indoor unit fan motor failure
Check Point 1 : Check rotation of Fan
Rotate the fan by hand when operation is off.
(Check if fan is caught, dropped off or locked motor)
>>If Fan or Bearing is abnormal, replace It.
OK
Check Point 2 : Check ambient temp. around motor
Check excessively high temperature around the motor.
(if there is any surrounding equipment that causes heat)
>>Upon the temperature coming down, restart operation.
OK
Check Point 3 : Check Indoor unit fan motor
Check Indoor unit fan motor. (PARTS INFORMATION 4)
>>if Indoor unit fan motor is abnormal, replace Indoor unit fan motor.
OK
Check Point 4 : Replace Controller PCB
If Check Point 1- 3 do not improve the symptom, replace Controller PCB.
Indicate or Display:
Indoor Unit : Operation lamp: 5 time Flash,
Timer lamp: 1 time Flash
Economy lamp : Continuous flash.
ERROR CODE : [E : 51]
Detective details:
When the fan motor speed is less than 1/3 of the target fan speed
for 56 seconds.
When detect the 0 rpm for 56 seconds after fan motor started.
2. Fan motor winding open
02-25
Outdoor unit :
POWER
ERROR
MODE
2
3. Motor protection by surrounding temperature rise
PUMP LOW PEAK
DOWN NOISE CUT
(L1) (L2) (L3) (L4) (L5) (L6)
15
5