Outdoor Air Temperature Sensor Anomaly - Mitsubishi Heavy Industries FDTC40ZSXVH Service Manual

Error code
E38
Remote control:
1. Applicable model
All models
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 -55°C or lower for 5
seconds continuously within 2
minutes to 2 minutes 20 seconds
after the compressor ON, the
compressor stops. After 3-minutes
delay, the compressor starts again
automatically, but if this anomalous
temperature is detected 3 times
within 40 minutes.
• When -55°C or lower is detected for
5 seconds continuously within 20
seconds after compressor ON.
4. Presumable cause
• Defective outdoor unit PCB
• Broken sensor harness or
temperature sensing section
(Check molding.)
• Disconnected wire connection
(connector)
Note:
LED Green Red
Keeps flashing Stays OFF
Indoor
- 8-time flash
Outdoor
5. Troubleshooting
Diagnosis
Is
the outdoor air
temperature sensor connector
connected properly?
YES
For the characteristics of outdoor air
temperature sensor, see the following graph.
Is the
characteristics of the
outdoor air temperature
sensor
OK?
Temperature-resistance characteristics
(Broken wire)
15
10
5
(Short-circuit)
0 10 20
Temperature (°C)
77
-
Content
Outdoor air temperature
sensor anomaly
NO
NO
YES
5kΩ at 25°C
30 40 50
-
'18 • PAC-SM-297
Countermeasure
Correct connector.
Defective outdoor
air temperature
sensor ➞ Replace.
Defective outdoor unit
PCB ➞ Replace.
(Defective outdoor air
temperature sensor input
circuit)