Discharge Pipe Temperature Sensor Anomaly - Mitsubishi FDT100VNXWVH Service Manual

Error code
Indoor control PCB
Remote control:
E39
Outdoor control PCB
Outdoor inverter
1. Applicable model
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 -10°C or lower for 5
seconds continuously within
10 minutes to 10 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.
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
discharge pipe
temperature sensor
connector connected
properly?
YES
Are the
characteristics
of discharge pipe
temperature
sensor
OK?
(Broken wire)
200
180
160
140
120
100
80
60
40
20
0
0
(Short-circuit)
Red
Content
Stays OFF
Discharge pipe temperature
1-time flash
Diagnosis
NO
For the characteristics of discharge pipe
temperature sensor, see the following graph.
NO
YES
Temperature-resistance characteristics
20 40 60 80 100 120
Temperature (°C)
114
- -
'20 • PAC-SM-351
sensor anomaly
Countermeasure
Correct connector.
Defective discharge pipe
temperature sensor ➞
Replace.
Defective outdoor
unit control (or main)
PCB ➞ Replace.
(Defective discharge pipe
temperature sensor input
circuit)
140 160