Service manual

Troubleshooting
Diagnostic Procedure for Check Code
87
14
Check code Operation cause
1. Ps sensor error
[b4]
2. Ps sensor connection error
Ps sensor alarm
3. Compressor error
Are Pd sensor/Ps sensor
correctly connected?
Are the output voltage
characteristics of Ps sensor
normal?
Check connection.
Pd sensor: CN501
Ps sensor: CN500
Check compressor.
Check indoor P.C. board.
If defective, replace.
Check external device.
If defective, replace.
Sensor error
Yes
No
No
Yes
Is the low-pressure below
0.95MPa during operation of
compressor?
No
Yes
Check interface P.C. board.
[
]
Check code Operation cause
[b5]
Indoor outside input alarm 1. External device error
[b6] 2. Indoor P.C. board error
Indoor outside interlock
Is the external device connected
to connector CN17?
Yes
No
Is the external device
operating normally?
No
Yes
Check cause of the operation.
Check code Operation cause
[b9]
Output voltage error of indoor pressure sensor
Indoor pressure sensor alarm
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 P.C. board.