Fujitsu ASU18RLF Service Instructions Manual page 82

Trouble shooting 37
No Operation (Power is ON)
Test 1 : Check indoor and outdoor installation condition
Indoor Unit - Check incorrect wiring between Indoor Unit - Remote Control.
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.
OK
Turn off Power and check/ correct followings.
Is there loose or removed communication line of Indoor unit and Outdoor unit?
OK
Test 2 : Check external cause at Indoor and Outdoor (Voltage drop or Noise)
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.
OK
Test 3 : Check Wired Remote Controller and Controller PCB
Check Voltage at terminal 1-3 of Controller PCB or Communication PCB.
(Power supply to Remote Control)
Compact Cassette, Slim Duct Type : CN14
Wall Mount , Floor Type : CN16
Compact Wall Mount Type : CNC01(UTY-XCBXZ2)
>> If it is DC12V, Remote Control is failure. (Controller PCB is normal)
>> If it is DC 0V, Controller PCB is failure.
>> Check Indoor unit fan motor. (SERVICE PARTS INFORMATION 5)
If it is normal, replace Controller PCB.
If it is abnormal, replace Indoor unit fan motor and Controller PCB.
>> If the symptom does not change by above Check 1, 2, 3, replace Main PCB of Outdoor unit.
(SERVICE PARTS INFORMATION 10)
Forecast of Cause :
1. Setting / Connection failure.
2. External cause.
3. Electrical components defective.
(Check Remote Control once again)
02-42
>> Replace Remote Control