Fujitsu AMUG24LMAS, Service Manual

Page: 75 / 200

Heat-exchanger outlet or middle temperature
thermistor short or open detected
1. Connector connection defective, open
2. Thermistor failure
3. Main PCB failure
OK
OK
Check Point 1 : Check the connector connection and cable open
Connector connection state check
Cable open check
Check Point 2 : Check thermistor
Thermistor characteristics check (Disconnect thermistor from PCB and check.)
03-27
Outdoor unit heat-exchanger liquid
temperature sensor error
Troubleshooting 20
Detective details:
Heat-exchanger liquid temperature thermistor
Detective actuators:
Forecast of cause:
Indicate or Display:
Indoor unit
Operation lamp: 7 times Flash,
Timer lamp : 3 times Flash
Wired remote control
Error code : [E : 73]
n: n times blinking
: Light ON : Light OFF
Mode Error
2 7
3
Outdoor unit (AOUG36/48LMAS1)
DC
CN65
AOU24RGLX
AOU30RGLX
THERMISTOR (HEX. PIPE.)
BL
AC
K
BL
AC
K
1 2 3
1 2 3
Check Point 3 : Check voltage of main PCB (DC5.0V)
Main PCB (CN65:1-3) voltage value = 5V (AOU24/30RGLX)
Main PCB (CN62:2-3) voltage value = 5V (AOUG36/48LMAS1)
Disconnect thermistor from main PCB, and check voltage.
If voltage does not appear, replace main PCB,
and execute check operation again.
(PARTS INFORMATION 7)
CN62
THERMISTOR
BL
AC
K
BL
AC
K
1 2 3
1 2 3
AOUG36LMAS1
AOUG48LMAS1
(HEX. PIPE.)
A B C D E F