Panasonic CS-ME5RKUA Service Manual page 66

12.4.30 F99 (DC Peak Detection)
Malfunction Decision Conditions
During startup and operation of cooling and heating, when inverter DC peak data is received by the outdoor internal
DC Peak sensing circuitry.
Malfunction Caused

DC current peak due to compressor failure.

DC current peak due to defective power transistor(s).

DC current peak due to defective outdoor unit PCB.

DC current peak due to short circuit.
Troubleshooting
When abnormality indication starts again.
Reset the error code and turn on the unit
again.
Is there a sound when compressor starts?
Is compressor vibration even?
Is there no change even if all refrigerant
is discharged?
Check the compressor winding resistance:
Turn off the power and disconnect
the harnesses U, V and W.
Measure the winding resistance
between U-V, V-W and W-U.
Are the compressor's winding resistance
(U-V, V-W or U-W) shorted?
NO (Compressor stops)
YES
NO (Quite a lot of vibration at
start operation)
YES
NO (Normal)
YES (Stops after 2, 3 seconds
of noise during operation)
NO (Normal)
YES
Outdoor electronic circuit defect due to
power transistor short.
Replace the outdoor unit PCB.
Amplification IC defect.
Diode defect.
Defect in microcontroller.
Replace the outdoor unit PCB.
Excessive amount of refrigerant.
For safety reason and to prevent component
breakdown, always switch off the power
before remove and connect the component.
Compressor defective due to
mechanical locked.
Replace compressor.
Compressor defective due to winding
shorted.
Replace compressor.
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