Inverter And Fan Motor Anomaly - Mitsubishi Heavy Industries FDT71VNXWVH Service Manual

Error code
Indoor control PCB
Remote control:
E51
Outdoor control PCB
Outdoor inverter
1. Applicable model
2. Error detection method
When power transistor anomaly
is detected for 15 minutes
continuously
3. Condition of error displayed
Same as above
4. Presumable cause
• Outdoor fan motor anomaly
• Inverter PCB anomaly
• Outdoor unit control (or main)
PCB anomaly
Note:
LED Green
Keeps flashing
Keeps flashing
Yellow LED
PCB
6-time flash
5. Troubleshooting
• Model FDC71VNX-W
detected between ② and ③
detected after disconnecting
outdoor fan motor?
Red
Content
Stays OFF

Inverter and fan motor anomaly

1-time flash
Diagnosis
⑴ ⑵
Is DC15V
on CNI3?
Note(1) Under anomalous conditions,
the voltage becomes less than
NO
DC14V.
⑴
Is DC15V
114
- -
'19 • PAC-SM-332
Countermeasure
Replace inverter PCB.
YES
If not solved, replace noise
filter PCB as well.
Replace outdoor fan motor.
YES
NO Replace outdoor unit
control PCB.
If not solved, replace
inverter PCB as well.