Mitsubishi Heavy Industries FDT71VNXVD Service Manual page 63

Error code
Remote controller: E7
1. Applicable model
All models
2. Error detection method
Anomalously low temperature
or high temperature (resistance)
is detected by indoor return air
temperature thermistor (Thi-A)
3. Condition of Error displayed
• When the temperature thermistor
detects -50 (-45)°C or lower for
5 (15) seconds continuously, the
compressor stops. After 3-minute
delay, the compressor starts again
automatically, but if this error
occurs again within 60 minutes
after the initial detection.
Note (1) Value in ( ) are for the
models SRK 50, 60.
4. Presumable cause
• Defective return air
temperature thermistor
connector
• Defective return air
temperature thermistor
• Faulty indoor control PCB
Note:
LED Green Red
Content
Indoor Keeps flashing 1 time flash
Keeps flashing Stays OFF
Outdoor
5. Troubleshooting
Diagnosis
Is the
connection of return
air temperature thermistor
connector OK?
YES
Are the
characteristics of return air
temperature thermistor
OK?
Temperature-resistance characteristic
(Broken wire)
15
10
5
(Shot circuit)
0

- -
Return air temperature
thermistor anomaly
NO
NO
YES
5k at 25 °C
10 20 30 40 50
Temperature (°C)
-
'10 • PAC-SM-137$
Countermeasure
Correct. Connect
connector.
Defective return air
temperature thermistor
Replace.
Defective indoor control
PCB Replace.
(Defective return air
temperature thermistor
input circuit)