Fujitsu AUXB04GALH Service Manual page 121

Trouble shooting 43
OUTDOOR UNIT Error Method:
Heat Ex. Liquid pipe Temp.
Sensor Error<TH5>
Detective Actuators:
Heat exchanger liquid temperature
thermistor
Forecast of Cause :
1. Connector connection defective, open
2. Thermistor defective
3. Main PCB defective
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 17".
OK
Check Point 3 : Check voltage of Main PCB (DC5.0V)
Main PCB (CN147:3-4) voltage value = 5V
Remove the thermistor from Main PCB, check the voltage.
CN147
Heat exchanger liquid temperature sensor (CN147:3-4)
If the voltage does not appear, replace Main PCB and set up orignal address. If the voltage does not appear, replace Main PCB and set up orignal address.
Indicate or Display:
E. 73.3
Outdoor Unit : E. 73. 3
Indoor Unit
Error Code
Detective details:
Heat exchanger liquid temperature thermistor short or open detected
1 2 3 4
1 2 3 4
: Operation LED 9 times Flash, Timer LED 15 Times Flash,
Filter LED Continuous Flash.
: 73
DC
04-51