Fujitsu AB*14LBAJ Service Instruction page 63

Trouble shooting 15
OUTDOOR UNIT Error Method:
CT error
Detective Actuators:
Outdoor Unit Main PCB Circuit
Outdoor Unit Filter PCB Circuit
(Input current sensor unit)
Forecast of Cause :
1. Defective connection of electric components 2. External cause 3. Filter PCB failure 4. Main PCB failure
Check Point 1-1 : Reset Power Supply and operate
Does Error indication show again?
YES
Check Point 2 :
Check connections of Outdoor Unit Electrical Components
Check if
the terminal connection
Check if connector is removed.
Check erroneous connection.
Check if cable is open.
>>Upon correcting the removed connector or mis-wiring,
reset the power.
OK
AO*18L/ 24L
Check Point 3 : Check Filter PCB and Main PCB
Check DC voltage of CN1 (between 2 (Brown) and 3 (Red)) on Filter PCB.
>> After 40seconds upon starting the Compressor,
If it is higher than 0.2V, Main PCB is failure. (Filter PCB is normal) >> Replace Main PCB
>> If it is lower than 0.2V, Filter PCB is failure.
If it does not improve the symptom, change Main PCB.
Check Point 4 : Replace Main PCB
If Check Point 1, 2 do not improve the symptom, change Main PCB.
Indicate or Display:
Refer to error code table.
Detective details:
When Input Current Sensor has detected lower than 0.5A
while Inverter Compressor is operating at higher than 56Hz,
after 1minute upon starting the Compressor.
(Except during the defrost operation)
is loose.
NO
Check Point 1-2 :
Check external cause at Indoor and Outdoor
(Voltage drop or Noise)
Instant drop : Check if there is a large load electric
Momentary power failure : Check if there is a defective
Noise : Check if there is any equipment causing harmonic
wave near electric line.(Neon bulb or electric
equipment that may cause harmonic wave)
Check the complete insulation of grounding.
>> Replace Filter PCB
02-25
apparatus in the same circuit.
contact or leak current in the
power supply circuit.