Component Tests and General Diagnostics
REFRIGERANT SYSTEM PERFORMANCE TEST1. Perform refrigerant charge check and refrigerant pressure check.
- If not as specified, troubleshoot refrigerant system.
- If they are correct, go to next step.
2. Place a dry-bulb thermometer in the driver-side center ventilator outlet.
3. Open the hood.
4. Warm up the engine and run it at a constant 1,500 rpm.
5. Set the fan switch to 4th speed.
6. Turn the A/C switch on.
7. Set the RECIRCULATE mode.
8. Set the temperature control to MAX COLD.
9. Set the VENT mode.
10. Close all the doors and all the windows.
11. Wait until the center ventilator temperature stabilizes. The output temperature is stable when the A/C compressor is repeatedly turned on and off based on the A/C compressor control of thermosensor.
12. Measure the center ventilator temperature.
13. Measure the ambient temperature.
14. Verify that the intersection of the center ventilator temperature and the ambient temperature is in the shaded zone.
- If not as specified, troubleshoot the refrigerant system.
REFRIGERANT PRESSURE CHECK
1. Install the manifold gauge set.
2. Warm up the engine and run it at a constant 1,500 rpm.
3. Set the fan switch to 4th speed.
4. Turn the A/C switch on.
5. Set the RECIRCULATE mode.
6. Set the temperature control to MAX COLD.
7. Set the VENT mode.
8. Close all the doors and all the windows.
9. Measure the ambient temperature and the high- and low-pressure side reading of the manifold gauge.
10. Verify that the intersection of the pressure reading of the manifold gauge and ambient temperature is in the shaded zone.
- If not as specified, troubleshoot the refrigerant system.
REFRIGERANT CHARGE CHECK
1. Install the manifold gauge set. (See Manifold Gauge Set Installation.)
2. Inspect the refrigerant pressure reading with the engine stopped.
3. Verify that the high- and low-pressure side readings of the manifold gauge are at 493 - 788 kPa {5.02 - 8.04 kgf/sq.cm, 72 - 114 psi}
- If the pressure readings are lower than specified, recharge the refrigerant amount.
- If the pressure readings are within the specification but there is insufficient cooling, go to the next step.
- If the pressure readings are within the specification and there is no leakage, the refrigerant amount is OK.
4. Start the engine and run it at a constant 2,000 rpm.
5. Turn the A/C switch on and set the fan switch to 4th speed.
6. Set the RECIRCULATE mode.
- If the A/C compressor is short-cycling, go to next step.
7. Verify the low-pressure side reading at which the magnetic clutch kicks out.
- If the pressure is 170 kPa {1.7 kgf/sq.cm, 24 psi} or lower, evacuate then recharge the refrigerant system with the proper amount of refrigerant.
- If the pressure is 210 kPa {2.1 kgf/sq.cm, 30 psi} or higher, inspect the thermosensor.