Refrigerant Pressure Sensor / Switch: Testing and Inspection

Refrigerant Pressure Sensor Circuit Check

Component Description

The refrigerant pressure sensor is installed at the condenser of the air conditioner system. The sensor uses an electrostatic volume pressure transducer to convert refrigerant pressure to voltage. The voltage signal is sent to ECM, and ECM controls cooling fan system.









Diagnosis Procedure

1. CHECK REFRIGERANT PRESSURE SENSOR OVERALL FUNCTION

1 Start engine and warm it up to normal operating temperature.
2 Turn A/C switch and blower switch ON.
3 Check voltage between ECM terminal 70 and ground with SDT or tester.











OK or NG
OK
INSPECTION END
NG
GO TO 2.

2. CHECK GROUND CONNECTIONS

1 Turn A/C switch and blower switch OFF.
2 Turn ignition switch OFF.
3 Loosen and retighten three ground screws on the body. Refer to [Power Supply and Ground Circuit Check] Power Supply and Ground Circuit Check.






OK or NG
OK
GO TO 3.
NG
Repair or replace ground connections.

3. CHECK REFRIGERANT PRESSURE SENSOR POWER SUPPLY CIRCUIT

1 Disconnect refrigerant pressure sensor harness connector.





2 Turn ignition switch ON.
3 Check voltage between refrigerant pressure sensor terminal 3 and ground with SDT or tester.











OK or NG
OK
GO TO 5.
NG
GO TO 4.

4. DETECT MALFUNCTIONING PART

Check the following.
- Harness connectors E5, F14
- Harness for open or short between ECM and refrigerant pressure sensor


Repair harness or connectors.

5. CHECK REFRIGERANT PRESSURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT

1 Turn ignition switch OFF.
2 Disconnect ECM harness connector.
3 Check harness continuity between refrigerant pressure sensor terminal 1 and ECM terminal 67.
Refer to Wiring Diagram.






4 Also check harness for short to ground and short to power.

OK or NG
OK
GO TO 7.
NG
GO TO 6.

6. DETECT MALFUNCTIONING PART

Check the following.
- Harness connectors E5, F14
- Harness for open or short between ECM and refrigerant pressure sensor


Repair open circuit or short to ground or short to power in harness or connectors.

7. CHECK REFRIGERANT PRESSURE SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1 Check harness continuity between ECM terminal 70 and refrigerant pressure sensor terminal 2.
Refer to Wiring Diagram.






2 Also check harness for short to ground and short to power.

OK or NG
OK
GO TO 9.
NG
GO TO 8.

8. DETECT MALFUNCTIONING PART

Check the following.
- Harness connectors E5, F14
- Harness for open or short between ECM and refrigerant pressure sensor


Repair open circuit or short to ground or short to power in harness or connectors.

9. CHECK INTERMITTENT INCIDENT

Refer to [Service Information for Electrical Incident: Intermittent Incident] Service Information for Electrical Incident: Intermittent Incident.

OK or NG
OK
Replace refrigerant pressure sensor. Refer to [Refrigerant Pressure Sensor: Removal and Installation] Service and Repair.
NG
Repair or replace.