Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

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LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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A/C System Performance Test

TEST DESCRIPTION
The following test measures the A/C system operating efficiency by comparing:
^ The ambient air temperature
^ The ambient air humidity
^ The pressure at the high-pressure side of the refrigeration system
^ The pressure at the low-pressure side of the refrigeration system
^ The temperature of the air being discharged into the passenger compartment

Step 1:




Steps 2-8:




The number(s) below refer to the step number(s) on the diagnostic table.
1. This step determines if there is enough refrigerant in the A/C system in order 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.