[B4] Low Pressure Sensor (Ps) Short Circuit; [B9] Indoor Pressure Sensor Short Circuit - Toshiba HFCR407C Service Manual

Check code
[b4]
Low pressure sensor (Ps) short circuit
Are Pd sensor/Ps sensor
correctly connected ?
Are the output voltage
characteristics of Ps sensor
Is the low pressure below
0.95MPa during operation of
compressor ?
Check interface PC board.
Check code
[b5]
External input display fault
[b6]
External interlock display fault
Is the external device connected
to connector CN17 ?
14
Is the external device
operating normally ?
Check cause of the operation.
Check code
[b9]
Indoor pressure sensor short circuit
There is an abnormal output voltage of indoor pressure sensor. Check connector (CN23) and output voltage
of the sensor.
If the sensor is normal, replace the indoor PC board.
Diagnostic procedure for check code
No
Yes
No
normal ?
Yes
No
Yes
No
Yes
No
Yes
Troubleshooting
Operation cause
1. Ps sensor error
2. Ps sensor connection error
3. Compressor error
Operation cause
1. External device error
2. Indoor PC board error
Operation cause
Output voltage error of indoor pressure sensor
102
Check connection.
Pd sensor: CN501
[ ]
Ps sensor: CN500
Sensor error
Check compressor.
Check indoor PC board.
If defective, replace.
Check external device.
If defective, replace.