Fujitsu AUXG45LRLB Service Instruction page 62

Trouble shooting 22
OUTDOOR UNIT Error Method:
Heat Ex. Outlet Temp.
Thermistor Error
Detective Actuators:
Heat exchanger liquid temperature
thermistor
Forecast of C ause :
1. Connector connection defective, open
2. Thermistor failure
3. Main PCB failure
Check Point 1 : Check the connector connection and cable open
Connector connection state check
Cable open check
OK
Check Point 2 : Check the thermistor
Thermistor characteristics check (Disconnect the thermistor from the PCB and check.)
* For the thermistor characteristics, refer to the "Service Parts Information 8".
OK
Check Point 3 : Check voltage of Main PCB (DC5.0V)
Main PCB 30/36(CN65:1-3) 45/54(CN63:1-2) voltage value = 5V
Remove the thermistor from Main PCB, check the voltage.
[30/ 36]
Compressor temperature thermistor(CN65:1-3)
If the voltage does not appear, replace Main PCB If the voltage does not appear,
the check operation again.
Indicate or Display:
Error code : 73
Detective details:
Heat exchanger outlet temperature thermistor short or open detected
3 2 1
3 2 1
CN65
Outdoor unit : Model 45.54
POWER
MODE
[45/ 54]
Compressor temperature thermistor(CN63:1-2)
, and execute
02-24
PUMP LOW PEAK
DOWN NOISE CUT
ERROR
L ( ) 1 L ( ) 2 (L3) (L4) (L5)
7 3
2
2 7 3
4 3 2 1
4 3 2 1
CN63
L ( ) 6
DC