Panasonic CS-E18NKUA Service Manual page 49

15.4.3 H16 (Outdoor Current Transformer Open Circuit)
Malfunction Decision Conditions
A current transformer (CT) is detected by checking the compressor running frequency (≥ rated frequency) and
CT detected input current (less than 0.65A) for continuously 20 seconds.
Malfunction Caused
CT defective
Outdoor PCB defective
Compressor defective (low compression)
Troubleshooting
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