Sinclair SCV-EB Series Service Manual page 70

5.24 P4 Troubleshooting
5.24.1 Digital display output
5.24.2 Description
 Compressor discharge temperature too high protection
 Error code is displayed on the refrigerant system PCB digital tube and user interface..
5.24.3 Procedure
High pressure switch protection
Discharge temperature sensor
connection on refrigerant system PCB is
Discharge temperature sensor has
short-circuited or failed
Replace refrigerant system PCB
Notes:
1. Discharge temperature sensor (Tp) connection is port CN4 on the refrigerant system PCB.
2. Measure sensor resistance. If the resistance is too low, the sensor has short-circuited. If the resistance is not consistent with the sensor's resistance
characteristics table, the sensor has failed.
68
P4
No
1
loose
No
2
No
Yes
Refer to P1 trouble shooting
Ensure the temperature sensor is
Yes
connected properly
Yes
Replace the sensor