Fujitsu AUXB04GALH Service Manual page 102

Trouble shooting 24
INDOOR UNIT Error Method:
Indoor unit suction air temp.
thermistor error (Outdoor Air unit )
Detective Actuators:
Indoor Unit Controller PCB Circuit
Suction air temp. Sensor
Forecast of Cause : 1. Connector defective connection 2. Thermistor defective 3. Controller PCB defective
Check Point 1 : Check connection of Connector
Check if connector is loose or removed
Check erroneous connection
Check if thermistor cable is open
>>Reset Power when reinstalling due to removed connector or incorrect wiring.
OK
Check Point 2 : Remove connector and check sensor resistance value
Sensor Characteristics (Rough value)
Temperature (°C)
Resistance Value (
Temperature (°C)
Resistance Value (
If Thermistor is either open or shorted, replace it and reset the power.
OK
Check Point 3 : Check voltage CN9 of Controller PCB (DC5.0V)
If the voltage does not appear, replace Controller PCB and set up the original address.
Indicate or Display:
E.4.A.1
Outdoor Unit : E.5 U.1
Error Code
Detective details:
When Indoor unit suction air temp. thermistor open or shortage is detected
0 5 1
)
33.6 25.2 20.1
4 0 4 5 5
) 5.3 4.3 3.5
: 4 A, 4 A. 1
0 1 5 2 0 2
15.8 12.5 10.0
0
04-32
5 30 35
8.0 6.5
DC