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A/C System Performance Test - HVAC System - Automatic

System Performance Test:




IMPORTANT: Be sure to record the relative humidity and ambient temperature conditions at the time of the test.

1. Park the vehicle inside or in the shade. The ambient temperature must be at least 16°C (60°F).
2. Open the windows and the doors.
3. Vent the engine exhaust.
4. Open the hood and install the high and low side pressure gauges.
5. Record the ambient temperature outside.
6. Record the relative humidity. Use a psychrometer or consult the local weather bureau.
7. Set the HVAC control assembly to recirculation (RECIRC) air mode with the blower speed set to highest position, the temperature to coldest position, the air flow to IP outlets and turn the A/C on.
8. Open the IP air outlet deflectors.
9. Place a thermometer in the right center IP outlet.
10. Place the transaxle in PARK and start the engine, stabilize engine at 2000 RPM.
11. Run the A/C system until the outlet air reaches the lowest temperature (about 3 minutes).
12. Record the outlet air temperature and the high side and low side pressures.
13. Turn the engine off and compare the readings with the upper limit data in the A/C Performance Table. Normally operating A/C system should not exceed levels shown.
14. If the readings exceed the table limits. Refer to VDOT A/C System Diagnosis. Initial Inspection and Diagnostic Overview
15. If equipped with C60 or CJ3 and the readings are under the table limits. Refer to Refrigerant System Checks. System Check - Refrigerant - HVAC System - Automatic
16. If equipped with CJ2 and the readings are under the table limits. Refer to Refrigerant System Checks.