Mitsubishi Electric FDT125VNVF Technical Manual page 450

Indoor display
Error code
E54
Remote controller:
inverter PCB
1. Applicable model
All models
2. Error detection method
When anomalous voltage
(pressure) is detected
3. Condition of Error displayed
If the pressure sensor detects 0V
or lower and 3.49V or higher for
5 seconds continuously within
2 minutes to 2 minutes 20
seconds after compressor ON,
the compressor stops. When
the compressor is restarted
automatically after 3-minuts
delay, if this anomaly occurs 3
times within 40 minutes
4. Presumable cause
• Defective low pressure sensor
connection
• Defective low pressure sensor
• Defective outdoor control
PCB
• Improper amount of
refrigerant
• Anomalous refrigeration
circuit
Note:
RUN light
–
Green LED
Outdoor
control PCB
Keeps flashing
Yellow LED
Outdoor
Keeps flashing
5. Troubleshooting
connection of low pressure
sensor connectors (at sensor side
measurement) matched with the value
indicated on the remote
Replace the low pressure sensor.
TIMER light
Content
–
Red LED
Low pressure sensor anomaly
1 time flash
Diagnosis
Are the
and PCB side) OK?
YES
Are the
pressure (actual
controller?
NO
Is
normal condition
restored?
449
- -
'12 • PAC-T-174
Countermeasure
Correct low pressure sensor
NO
connector connection.
Is refrigerant amount
YES
charged properly?
Is there any anomaly on the
refrigeration circuit?
Defective outdoor control
NO
PCB ➞ Replace.
(Defective low pressure
sensor input circuit)
OK
YES