Mitsubishi Electric FDT125VNVF Technical Manual page 403

Error code
Indoor control PCB
E51
Remote controller:
Outdoor control PCB
Outdoor inverter
1. Applicable model
All models
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 control PCB anomaly
Note:
LED Green
Keeps flashing
Keeps flashing
Yellow LED or Red LED Green LED
PCB
6 times flash or 2 times flash
5. Troubleshooting
• Model FDC100-140VN
detected between ② and ③
detected after disconnecting
outdoor fan motor?
• Model FDC100-140VS and FDC200, 250VS
Replace immediately the inverter PCB and the power transistor.
Note(2) How to check the voltage between ② and ③ of CNI3?
Red
Content
Stays OFF
1 time flash
Inverter and fan motor anomaly
Keeps flashing
Diagnosis
⑴ ⑵
Is DC15V
on CNI3?
Note(1) Under anomalous conditions,
the voltage becomes less than
NO
DC14V.
⑴
Is DC15V
402
- -
'12 • PAC-T-174
Countermeasure
Replace inverter PCB
YES
If not solved, replace
Noise filter PCB as well.
Replace outdoor fan motor.
YES
Replace outdoor control
NO
PCB
If not solved, replace
inverter PCB as well.
② ： 15V (＋)
③ ： GND (−)
③
②