Mitsubishi FDT71VH - Outdoor Air Temperature Sensor Anomaly

-
113
-
'20 • PAC-SM-351
Error code
Remote control:
LED Green Red
Outdoor control PCB
Outdoor inverter
PCB
1-time flash Keeps flashing
Indoor control PCB
Stays OFFKeeps flashing
Content
Keeps flashing
Yellow LED
Outdoor air temperature
sensor anomaly
E38
1. Applicable model
5. Troubleshooting
Diagnosis Countermeasure
Is
the outdoor air
temperature sensor connector
connected properly?
YES
Is the
characteristics of the
outdoor air temperature
sensor
OK?
NO
For the characteristics of outdoor air
temperature sensor, see the following graph.
YES
0
5
10
15
20
25
30
35
01020304050
NO
Temperature-resistance characteristics
Temperature (°C)
(Broken wire)
(Short-circuit)
Temperature sensor resistance (kΩ)
Correct connector.
Defective outdoor
air temperature
sensor
➞
Replace.
Defective outdoor
unit control (or main)
PCB
➞
Replace.
(Defective outdoor air
temperature sensor
input circuit)
2. Error detection method
Detection of anomalously low
temperature (resistance) on
outdoor air temperature sensor
3 . Condition of error displayed
• When the temperature sensor
detects -45°C or lower for 5
seconds continuously within 2
minutes to 2 minutes 20 seconds
after the compressor ON, the
compressor stops. After 3-minute
delay, the compressor starts again
automatically, but if this anomalous
temperature is detected 3 times
within 40 minutes.
• When -45°C or lower is detected for
5 seconds continuously within 20
seconds after compressor ON.
4. Presumable cause
• Defective outdoor unit control
(or main) PCB
• Broken sensor harness or
temperature sensing section
(Check molding.)
• Disconnected wire connection
(connector)
Note: