Performance Test - Service Stall

IMPORTANT:
^ If ambient air temperature is lower than 0° C (32°F), A/C compressor will not be enabled.
^ This test must be performed in a service stall environment that protects the vehicle from wind that could cause incorrect pressure/temperature readings.




1. Open hood and leave open during entire test.
2. Install a manifold gauge set to high and low side service ports.
3. Start engine.




4. Turn A/C Off - A/C button indicator light Off.
5. Depress re-circulation button so that indicator light is lit.
6. Install thermometer into right center outlet.
7. Set mode knob to I/P outlet position - full counter-clockwise.
8. Set temperature knob to full cold position - full counter-clockwise.
9. Set blower to third speed - M2.
10. Open both front doors and windows to stabilize interior air temperature with outside ambient temperature.

IMPORTANT: A Tech 2 with version 19.005 or higher software is required to perform this test.

11. Connect Tech 2 to data link connector (DLC).
12. Using the Tech 2, verify engine is operating at thermostat control temperature ECT is 188°F or greater.
13. Use the appropriate Tech 2 special function to set engine cooling fan speed to medium.
a. Select HVAC Performance special function and press enter. Display should indicate fans are operating at MED.
b. Turn A/C On - A/C button indicator light On.

IMPORTANT: Allow A/C system pressures to stabilize before beginning test.

c. Using Tech 2, increase engine speed to 2000 rpm.
14. Record A/C system pressures and outlet temperature every minute for five minutes.
15. Release throttle to return engine to idle.
16. Release Tech 2 control of engine cooling fans.
17. Compare recorded values to system performance charts then continue down diagnostic flow chart. Diagnostic Flow Chart