You can go to the auto parts store, but. A can of R 134 with a gauge and hose attached, open the vehicle hood and look for the Low port on the AC system....should be easy to find....unscrew the cap .....then make sure your engine is running with full AC on maximum. Check temp of the day as it will affect the pressure. Adjust the range dial if needed, then Snap on the hose connector. Shake the can, upside down. If your dial,shows in the green then you wont need to add, or you can add a little if the AC feels less cold than normal. Repeat as necessary based upon pressure reading and the coolness in the vehicle and the vehicle pressure specs......this is a super easy process. If the issue of losing coolness continues then take it in to a mechanic......
Go to google year make model video will show
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