Component Tests and General Diagnostics
REFRIGERANT SYSTEM PERFORMANCE TESTNOTE: After servicing the refrigerant system, test its performance.
1. Install the manifold gauge set.
2. Open the hood.
3. Close all the doors and all the windows.
4. Warm up the engine and run it at a constant 1,500 rpm.
5. Turn the A/C switch on.
6. Set the fan switch at 4th.
7. Set the REC/FRESH lever to REC.
8. Set the mode dial to VENT.
9. Set the temperature control dial to MAX COLD.
10. Measure the center ventilator temperature and record the temperature reading.
11. Measure the ambient temperature and record the temperature reading.
12. Verify that the temperature reading is in the shaded zone (maximum 6 °C {43 °F}).
- If the performance is not within the shaded zone, troubleshoot the refrigerant system.
REFRIGERANT CHARGE CHECK
1. Install the manifold gauge set.
2. Check 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. (See REFRIGERANT CHARGING.)
- 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 are no leaks, the refrigerant amount is OK.
4. Start the engine and run it at a constant 2000 rpm.
5. Turn the A/C switch on and set the fan switch at 4th.
6. Set the REC/FRESH lever to REC.
- If the A/C compressor is short-cycling, note the low-pressure side reading at which the magnetic clutch kicks out.
- If the pressure is 167 kPa {1.7 kgf/sq.cm, 24 psi} or lower, evacuate then recharge the refrigerant system with the proper amount of refrigerant. (See REFRIGERANT CHARGING.)
- If the pressure is 206 kPa {2.1 kgf/sq.cm, 30 psi} or higher, inspect the thermoswitch. (See THERMOSWITCH INSPECTION.)
REFRIGERANT PRESSURE CHECK
1. Install the manifold gauge set.
2. Open the hood.
3. Close all the doors and all the windows.
4. Warm up the engine and run it at a constant 1,500 rpm.
5. Turn the A/C switch on.
6. Set the fan switch to 4th speed.
7. Set the REC/FRESH lever to REC.
8. Set the mode dial to VENT.
9. Set the temperature control dial to MAX COLD.
10. Measure the high- and low-pressure side readings of the manifold gauge.
- It the high- and low-pressure side readings are in the shaded zones as shown in the figure, the refrigerant system is normal.
- If the high- and low-pressure side readings are not as specified, troubleshoot the refrigerant system.