Fujitsu AOU18RLB - Indoor Room Thermistor Error

Check Point 3 : Check voltage of Controller PCB (DC5.0V)
Make sure circuit diagram of indoor unit and check terminal voltage at Thermistor (DC5.0V)
If the voltage does not appear, replace Controller PCB.
THERMISTOR
(ROOM TEMP.)
THERMISTOR
(PIPE TEMP.)
BLACK
CN3
1
2
1
2
1
2
1
2
BLACK
BLACK
BLACK
WHITE
RED
1
2
3
1
2
3
CN1
Trouble shooting 5
INDOOR UNIT Error Method:
Detective Actuators:
Detective details:
Forecast of Cause :
Check Point 2 : Remove connector and check Thermistor resistance value
Check Point 1 : Check connection of Connector
10.012.515.820.225.933.644.058.2Resistance Value (k )
Temperature (°F)
OK
OK
5.36.58.0Resistance Value (k )
Temperature (°F)
Indoor Room Thermistor Error
Indoor unit Controller PCB
Room temperature thermistor
When Room Temperature Thermistor open or short-circuit is detected.
1. Connector connection failure 2.Thermistor failure 3. Controller PCB failure
Check if connector is removed.
Check erroneous connection.
Check if thermistor cable is open.
>>Upon correcting the removed connector or miss-wiring, reset the power.
Thermistor Characteristics (Approx. value)
If Thermistor is either open or shorted, replace it and reset the power.
77°F68°F59°F50°F41°F32°F23°F14°F
104°F
4.4
113°F95°F86°F
Indicate or Display:
02-08
Outdoor Unit : No indication
Indoor Unit : Operation lamp: 4 time Flash, Timer lamp: 1 time Flash
Economy lamp: Continuous flash.
ERROR CODE : [E : 41]