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A/C System Performance Test




Air Conditioning (A/C) System Performance Test (Diesel Engine)


This test measures the operating efficiency of the A/C system under the following conditions:
The current ambient air temperature
The current relative humidity
The high side pressure of the A/C system
The low side pressure of the A/C system
The temperature of the air being discharged into the passenger compartment



Step 1:




Steps 2 - 3:




Steps 4 - 8:






Test Description
The numbers below refer to the step numbers on the diagnostic table.
1. This step determines if the A/C system has at least the minimum refrigerant charge required to operate the system without damage.
2. This step measures the performance of the A/C system.
3. This step is to allow for vehicle variations as well as high ambient air temperatures.





A/C Performance Table: