Heating and Air Conditioning: Testing and Inspection
PERFORMANCE TEST
1) Confirm that vehicle and environmental conditions are as follows.
- Vehicle is not exposed to direct sun.
- Ambienttemperature is within 15°C-35°C (59°F-95°F).
2) Connect high and low side charging hoses of manifold gauge to hose fittings of A/C component.
3) Warm up engine to normal operating temperature and keep it at specified idle speed.
4) Turn A/C switch ON, and set blower switch at "HI", temperature lever at "COOL", fresh/circulation control lever at "CIRCULATION". (Confirm that A/C compressor and condenser fan are working.)
5) Keep all windows, doors and engine food open.
6) With about 20 mm (0.8 in.) of dry bulb thermometer inserted into center duct air outlet and another one set near evaporator air inlet, read temperature indicated on each thermometer.
SE SERIES
7) Check for each pressure of low side and high side if it is within shaded range of left graph.
NOTE: Pressure registered on gauge varies with ambient temperature. Therefore, use left graphs when determining if pressures are normal or not.
If each gauge reading is out of specified pressure, correct defective part referring to following Diagnosis table.
8) Check inlet port temperature-to-outlet port temperature relationship using graph at the left.
For example, if evaporator inlet port temperature is 25°C (77°F) and center duct air outlet temperature is 11°C (51.8°F), their crossing point is within acceptable range as shown in graph at the left.
In this case, cooling performance is satisfactory and proper.
9) If crossing point is out of acceptable range, diagnose trouble referring to following Diagnosis table.
SZ SERIES
7) Check for each pressure of low side and high side if it is within shaded range of left graph.
NOTE: Pressure registered on gauge varies with ambient temperature. Therefore, use left graphs when determining if pressures are normal or not.
If each gauge reading is out of specified pressure, correct defective part referring to following Diagnosis table.
8) Check inlet port temperature-to-outlet port temperature relationship using graph at the left.
For example, if evaporator inlet port temperature is 25°C (77°F) and center duct air outlet temperature is 8.5°C (47.3°F), their crossing point is within acceptable range as shown in graph at the left.
In this case, cooling performance is satisfactory and proper.
9) If crossing point is out of acceptable range, diagnose trouble referring to following Diagnosis table.