Mazda CX-9 Grand Touring 2009 Manual page 1737

7. Open the high-pressure side valve of the manifold gauge and charge with refrigerant until the weight of
refrigerant tank has decreased 330-355 g {11.7-12.5 oz} from the amount in Step 2.
Fig. 8: Opening High-Pressure Side Valve Of Manifold Gauge
Courtesy of MAZDA MOTORS CORP.
8. Close the low-pressure side valve of the manifold gauge.
WARNING:
9. Start the engine and actuate the A/C compressor.
10. Open the low-pressure side valve of the manifold gauge and charge with refrigerant until the weight of
the refrigerant tank has decreased regular amount from the amount in Step 2.
2008 Mazda CX-9 Grand Touring
2008 HVAC Refrigerant System - Mazda CX-9
the cans could explode, scattering metal fragments and liquid
refrigerant that can seriously injure you. Therefore, do not open
the high-pressure side valve while the engine is running.
If charging the system with refrigerant using service cans,
running the engine with the high-pressure side valve open is
dangerous. Pressure within the service cans will increase and
the cans could explode, scattering metal fragments and liquid
refrigerant that can seriously injure you. Therefore, do not open
the high-pressure side valve while the engine is running.
Fig. 9: Closing Low-Pressure Side Valve Of Manifold Gauge
Courtesy of MAZDA MOTORS CORP.