A/C System Leak Tests

WARNING: Review the Service Precautions before leak testing the system.

If the air conditioning system is not cooling properly. determine if the refrigerant system is fully charged. See A/C Performance Testing. If the refrigerant system is low or empty, a leak at a line, fitting, or component seal is likely. Fittings, lines, or components that appear to be oily indicate a possible refrigerant leak. To detect a leak in the refrigerant system, perform one of the following procedures:

SYSTEM EMPTY
1. Evacuate the refrigerant system. See Refrigerant System Evacuate.
2. Connect and dispense 0.283 kPa (0.6 lbs. or 10 oz.) of R-134a refrigerant into the evacuated refrigerant system. See Refrigerant System Charge.
3. Position the vehicle in a wind-free work area. This will aid in detecting small leaks.
4. With the engine not running, use a electronic R-134a leak detector and search for leaks. Move the leak detector probe slowly along the bottom side of all lines and fittings, because R-134a is heavier than air.
5. To inspect the evaporator coil for leaks, insert the leak detector probe into the center panel outlet. Set the blower motor switch to the lowest speed (A/C) position, and the mode control switch in the Recirculation mode.

SYSTEM LOW
1. Position the vehicle in a wind-free work area. This will aid in detecting small leaks.
2. Bring the refrigerant system up to operating temperature and pressure. This is done by allowing the engine to run with the air conditioning system on for five minutes.
3. With the engine not running, use a electronic R-134a leak detector and search for leaks. Move the leak detector probe slowly along the bottom side of all lines and fittings, because R-134a is heavier than air.
4. To inspect the evaporator coil for leaks, insert the leak detector probe into the center panel outlet. Set the blower motor switch to the lowest speed (A/C) position, and the mode control switch in the Recirculation mode.