Compressor HVAC: Testing and Inspection

1. Install manifold gauge set.
2. Run engine at fast idle.
3. Check compressor for following:
a. High pressure gauge reading is not lower and low pressure gauge reading is not higher than normal.
b. Metallic sound
c. Leakage from shaft seal.

If defects are found, repair the compressor.

4. Check magnetic clutch.
a. Inspect the pressure plate and the rotor for signs of oil.
b. Check the clutch bearings for noise and grease leakage.





c. Using an ohmmeter, measure the resistance of the stator coil between the clutch lead wire and ground.
Standard resistance: 2.7 - 3.1 at 20°C (68°F)

If resistance is not as specified, replace the coil.





5. Revolution detecting sensor. Using an ohmmeter, measure the resistance between two terminals of the sensor.
Standard resistance: 100 - 130 Ohms at 2O°C (68°F)

If resistance is not as specified, replace the revolution detecting sensor.