Outdoor Air Temperature Sensor Anomaly - Mitsubishi FDT100VNXWVH Service Manual

Error code
Indoor control PCB
Remote control:
E38
Outdoor control PCB
Outdoor inverter
1. Applicable model
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:
LED Green
Keeps flashing
Keeps flashing
Yellow LED
PCB
Keeps flashing
5. Troubleshooting
Is
the outdoor air
temperature sensor connector
connected properly?
YES
Is the
characteristics of the
outdoor air temperature
sensor
OK?
Temperature-resistance characteristics
(Broken wire) 35
30
25
20
15
10
5
0
(Short-circuit)
0
Red
Content
Stays OFF
Outdoor air temperature
1-time flash
Diagnosis
NO
For the characteristics of outdoor air
temperature sensor, see the following graph.
NO
YES
10 20 30 40 50
Temperature (°C)
113
- -
'20 • PAC-SM-351
sensor anomaly
Countermeasure
Correct connector.
Defective outdoor
air temperature
sensor ➞ Replace.
Defective outdoor
unit control (or main)
PCB ➞ Replace.
(Defective outdoor air
temperature sensor
input circuit)