Finding Leaks Via Vacuum Test Using A/C Service Station Or Nitrogen Pressure Testing

WARNING: This page is about a different car, the 2024 Audi SQ7, 2024 Audi Q7, 2023 Audi SQ7, and 2023 Audi Q7. However, it is still accessible from the selected car via links, so may be relevant.

Vehicles with a high-voltage system (hybrid vehicles)

-- On vehicles with a high-voltage system, switch off (deactivate) the "auxiliary climate control" function. Refer to the Owner's Manual and Infotainment/MMI Operating Manual.

All Vehicles

-- Switch off the ignition.

Finding leaks via the vacuum test using the A/C service station or nitrogen pressure testing. Refer to Refer to REFRIGERANT CIRCUIT, EVACUATING WITH A/C SERVICE STATION .

NOTE:

Small leaks (less than 100 g (3.5 oz) of refrigerant loss per year) are not often detected with the vacuum test or with the nitrogen pressure test. The incoming air and the amount of nitrogen flowing out is too small to be able to locate the faulty location based on noise.

Leaks on the refrigerant circuit that are greater than 100 g (3.5 oz) of refrigerant loss each year are also not always detectable with the vacuum test or with the nitrogen pressure test, depending on the ambient conditions (ambient noise, leak location etc.). The incoming air and/or the amount of nitrogen flowing out may be too small to generate any noise that would indicate a faulty location.

Depending on the ambient conditions, larger refrigerant circuit leaks (such as stone impact to the condenser with a refrigerant loss greater than 100 g (3.5 oz) per day) can be detected, for example, by noises that are produced during the vacuum test or the nitrogen pressure testing at the faulty location. Refer to Refer to REFRIGERANT CIRCUIT, EVACUATING WITH A/C SERVICE STATION .