Fujitsu AS G07KMTA Series Service Instruction page 39

Trouble shooting 10
INDOOR UNIT Error Method:
Indoor Heat Ex. Thermistor Error
Detective Actuators:
Indoor unit Main PCB
Heat Ex. temperature thermistor
Forecast of Cause :
1. Connector connection failure
Check Point 1 : Check connection of Connector
Check if connector is removed.
Check erroneous connection.
Check if thermistor cable is open.
>>Upon correcting the removed connector or mis-wiring, reset the power.
OK OK
Check Point 2 : Remove connector and check Thermistor resistance value Check Point 2 :
Thermistor Characteristics (Approx. value)
Temperature
Resistance Value (k )
Temperature
Resistance Value (k )
If Thermistor is either open or shorted, replace it and reset the power.
OK
Check Point 3 : Check voltage of Main PCB (DC5.0V)
Make sure circuit diagram of indoor unit and check terminal voltage at Thermistor (DC5.0V)
THERMISTOR
(PIPE)
BLACK
BLACK
BLACK
BLACK
THERMISTOR
(ROOM TEMP.)
If the voltage does not appear, replace Main PCB.
Indicate or Display:
Outdoor Unit : No indication
Indoor Unit
ERROR CODE : [E : 42 ]
Detective details:
When Heat Ex. Temperature Thermistor open or short-circuit is detected.
2.Thermistor failure
-30°C -20°C -10°C
1131.9 579.6 312.3
30°C 40°C 50°C
39.6 25.6 17.1
1 1
2 2
CN4
3 3
4 4
: Operation lamp: 4 time Flash, Timer lamp: 2 time Flash
Economy lamp: Continuous flash.
3. Main PCB failure
-5°C 0°C 5°C
233.2 176.0 134.2
60°C 63°C
11.6 10.4
02-13
10°C 20°C
103.3 62.9