Fujitsu AUXB04GALH Service Manual page 95

Trouble shooting 17
INDOOR UNIT Error Method:
Indoor Unit power supply error for
FAN motor 1 (Outdoor Air unit)
Detective Actuators:
Indoor Unit Controller PCB Circuit
Indoor Unit filter PCB Circuit
Forecast of Cause :
1. Noise momentary open, voltage drop
4.
Check Point 1 : Check if any outside cause such as voltage drop or noise
Instant voltage drop ----- Check if there is any electric equipment with a large load within the same circuit.
Momentary power failure ----- Check contact failure or leak current in power supply circuit
Check if there is any equipment that causes harmonic wave near the power cable (Neon light bulb or any electronic equipment which
causes harmonic wave). And check the complete insulation of grounding.
>>If the same symptom does not reappear after resetting the power, possibility of noise is high.
OK
Check Point 2 : Check wire connection
Wire lose connection / damage between the CN21on the Controller PCB and CN250 on the Filter PCB
In case of Model 72, between W530 (W531) on the filter PCB and capacitor.
>>If there is abnormal on the wire, replace it
OK
Check Point 3 : Check rotation of Fan / wire resistance
Rotate the applicable fan by hand when operation is off.
Disconnect the connector from the controller PCB and Check resistance value of Motor connector
OK
Check Point 4 : Check peripheral devices, Posistor, Capacitor, Diode bridge
Check resistance value, short circuit, visible damage
>>If there is abnormal , replace it
OK
Check Point 5 : Replace Filter PCB
Change filter PCB
NG
Check Point 6 : Replace Controller PCB
Change Controller PCB and set up the original address.
Indicate or Display:
E.39.1
Outdoor Unit : E.5 U.1
Error Code
Detective details:
When the DC power input for Fan motor < W500 - W501 on
the Filter PCB> becomes lower voltage than the specified voltage.
Peripheral electric devices
: 39.1
2. Wire connection
5. Filter PCB 6. Controller PCB
04-25
3. Fan motor