Mitsubishi Heavy Industries SCM71ZM-S1 Technical Manual page 271

Error code
E39
Remote control:
1. Applicable model
All models
2. Error detection method
Detection of anomalously low
temperature (resistance) on
the discharge pipe temperature
sensor
3. Condition of error displayed
When the temperature sensor
detects -25 °C or lower for 5
seconds continuously within
10 minutes to 10 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.
4. Presumable cause
• Defective outdoor main
(control) 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
discharge pipe
temperature sensor
connector connected
properly?
YES
Are the
characteristics
of discharge pipe
temperature
sensor
OK?
Temperature-resistance characteristics
(Broken wire)
100
50
0
[T 90 ]
°C
0 20
(Short circuit)
270
-
Content
Discharge pipe
temperature sensor anomaly
NO
For the characteristics of discharge pipe
temperature sensor, see the following graph.
NO
YES
40 60 80 100 120
Temperature (°C)
-
'17 • SCM-T-225
Countermeasure
Correct connector.
Defective discharge pipe
temperature sensor ➞
Replace.
Defective outdoor main
(control) PCB ➞ Replace.
(Defective temperature
sensor input circuit)
140