Panasonic CS-E7PKR Service Manual page 141

16.4.29 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
Note: Some error code might not applicable for this model.
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