Fujitsu AB Series A18LATN, Service Instruction

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Trouble shooting 33
Forecast of Cause:
Check Point 2 : Check external cause at Indoor and Outdoor (Voltage drop or Noise)
Check Point 1 : Check indoor and outdoor installation condition
Check Point 3 : Check Electrical Components at Indoor and Outdoor
OK
OK
OK OK
No Operation (Power is ON)
1. Setting/ Connection failure 2. External cause
3. Electrical Component defective
Indoor Unit - Check incorrect wiring between Indoor Unit - Remote Control, or terminals between Indoor Units.
Or, check if there is an open cable connection.
Are these Indoor Unit, Outdoor Unit, and Remote Control suitable model numbers to connect?
>> If there is some abnormal condition, correct it by referring to Installation manual and
Data & Technical Manual.
Turn off Power and check/ correct followings.
Is there loose or removed communication line of Indoor Unit and Outdoor Unit?
Instant drop ----- Check if there is a large load electric apparatus in the same circuit.
Momentary power failure ----- Check if there is a defective contact or leak current in the power supply circuit.
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.
>> If it is DC12V, Remote Control is failure. (Controller PCB is normal) >> Replace Remote Control
>> If it is DC 0V, Controller PCB is failure. (Check Remote Control once again) >> Replace Controller PCB
>> If the symptom does not change by above Check 1, 2, 3, replace Main PCB of Outdoor unit.
07-34
Check Voltage at CN14 of Controller PCB.
(Power supply to Remote Control)