A/C System Performance Test - HVAC System - Manual

System Performance Test

TOOLS REQUIRED
^ J 6742-03 Thermometer Dial
^ J39183-C R-134a Manifold Gauge Set

IMPORTANT: Perform this test only under the following conditions:
^ The vehicle is not exposed to direct sunlight.
^ The ambient temperature is within 15-35°C (59-95°F).

1. Turn the ignition switch to the LOCK position.
2. Apply the parking brake.
3. Connect J39183-C manifold gauge set, high side (red) and the low side (blue) hoses to the appropriate service ports on the vehicle.
4. Set the air mode to the VENT position.
5. Set the fresh/recirc lever to the RECIRC position.
6. Set the temperature control to full COLD.
7. Start the engine. Warm the engine up to the normal operating temperature. Let the engine run at the normal idle speed.
8. Set the blower speed to the HIGH position.
9. Press the Air Conditioning (A/C) switch to the ON position.
Place J 6742-03 thermometer dial probe, through the Instrument Panel (IP) center outlet.
10. Open all of the doors, the windows and the hood.
11. Monitor J 39183-C manifold gauge set. Record the refrigerant pressures when the pressures stabilize.
12. Monitor J 6742-03 thermometer. Record the center outlet air temperature when the temperature stabilizes.
13. Turn the blower speed selector to the OFF position.
14. Turn the ignition switch to the LOCK position.
15. Remove J 6742-03 thermometer.
16. Disconnect J39183-C manifold gauge set.

Compare the recorded high and the low refrigerant system pressures and the outlet air temperature with the graph below. If the values are not within the specifications, refer to TXV A/C System Diagnosis (Insufficient Cooling).