Self-Diagnosis Method - Panasonic CS-E9RKUAW Service Manual

18.4 Self-diagnosis Method

18.4.1 H11 (Indoor/Outdoor Abnormal Communication)
Malfunction Decision Conditions

During startup and operation of cooling and heating, the data received from outdoor unit in indoor unit signal
transmission is checked whether it is normal.
Malfunction Caused

Faulty indoor unit PCB.

Faulty outdoor unit PCB.

Indoor unit-outdoor unit signal transmission error due to wrong wiring.

Indoor unit-outdoor unit signal transmission error due to breaking of wire in the connection wires between the
indoor and outdoor units.

Indoor unit-outdoor unit signal transmission error due to disturbed power supply waveform.
Troubleshooting
When abnormality indication starts again.
Check the indoor-outdoor units' connection wires.
Is there any wiring error?
Disconnect terminal 3 wire and measure Vdc between terminal
2 & 3 from the outdoor unit.
Is the Vdc fluctuate between 10~70 Vdc?
Reconnect terminal 3 wire and measure Vdc between terminal
2 & 3 from the outdoor unit.
Is the Vdc fluctuate between 10~70Vdc?
NO
YES
78
For safety reason and to prevent
component breakdown, always switch
off the power before remove and
connect the component.
YES
Correct the indoor-outdoor units
connection wires.
NO
Replace outdoor PCB.
NO
Replace indoor unit PCB.