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Refrigerant Pressure Sensor / Switch: Testing and Inspection





HEATING / AIR CONDITIONING: AIR CONDITIONING PRESSURE SENSOR: ON-VEHICLE INSPECTION

1. INSPECT NO. 1 PRESSURE SWITCH (for Single Air Conditioning System)

(a) Install a manifold gauge set.





Text in Illustration





(b) Connect the positive (+) lead of the ohmmeter to terminal 1 and the negative (-) lead to terminal 2.

(c) Check the resistance between the terminals when refrigerant pressure is charged as shown in the illustration.

If resistance is not as specified, replace the No. 1 pressure switch.

2. INSPECT AIR CONDITIONING PRESSURE SENSOR (for Dual Air Conditioning System)

(a) Install a manifold gauge set.

(b) Disconnect the connector from the air conditioning pressure sensor.

(c) Connect the positive (+) lead of a DC 5 V power source to terminal 3 and the negative (-) lead to terminal 1.





(d) Connect the positive (+) lead of the voltmeter to terminal 2 and the negative (-) lead to terminal 1.

(e) Measure the voltage according to the value(s) in the table below.

Standard Voltage:





Text in Illustration





If the result is not as specified, replace the air conditioning pressure sensor.