System Performance Test

Pressure/Temperature Relationship Table:

Tool Required:
J 21213-A Four Jack-Dual Range Temperature Tester or Equivalent

1. Park the vehicle inside or in a shaded area.
2. Open doors or windows to ventilate the interior.
3. Vent the engine exhaust, if necessary.
4. Open the hood and install high and low side pressure gauges. Route lines over the rear hood seal and tape the gauges to the windshield for viewing.
5. Close the hood.
6. Record the ambient temperature at the vehicle.
7. Record the relative humidity. Use a psychrometer to measure atmospheric moisture or consult the local weather bureau.

Important
- Make sure to record the relative humidity and ambient temperature conditions at the time of the test.

8. Close the doors or windows.
9. Set the mode knob to NORM A/C, blower switch on HIGH, and temperature knob on full BLUE (Cold).
10. Open the air conditioning outlets.
11. Install J 21213-A or equivalent into the right center air conditioning outlet.
12. Place the transmission in PARK or NEUTRAL.
13. Start the engine, stabilize engine speed at 2000 RPM, and start the timer.
14. Run the air conditioning system until the outlet air reaches the lowest temperature (about 3 minutes).
15. Record the outlet air temperature and high-side arid low-side pressures.
16. Turn the engine off and compare the readings. Normally operating air conditioning systems should not exceed the levels shown on the Pressure Temperature Relationship and System Performance Test tables.

If a malfunction is suspected due to abnormal system pressures, inspect the following:

Inspect

1. Outer surfaces of radiator and condenser cores to make sure airflow is not blocked by dirt, leaves, or other foreign material. Make sure to check between the condenser and radiator as well as the outer surfaces.
2. Evaporator core, condenser core, hoses, tubes, etc., for restrictions or kinks.
3. Refrigerant leaks.
4. Air ducts for leaks or restrictions. A low airflow rate may indicate a restricted evaporator core.
5. Compressor clutch for slippage.
6. Drive belt for improper tension.
7. Accumulator for plugging.
8. Expansion (orifice) tube for plugging.

If the problem is not found, continue with the A/C Performance Charts for the CCOT system. [1][2]Component Tests and General Diagnostics