Ok today we are going to talk about recharging the AC system on this Nissan Maxima. We want to start with taking the low side pressure service valve, remove the cap and connect the low side service. From here we are going to take the high side and repeat the process. Now we are going to recover the existing freon that's in the system if there is any, by simply hitting the recover button on the machine. Once the recovery process is complete now we must evacuate the system. The reason we are doing that is we are taking the air out of the entire system that's closed for the air conditioner. The reason for that is the moisture in the air will mix with the freon and create an acid which will cause you problems down the road. At this point we are going to evacuate the system which is right here the vacuum switch. Once the system is pulled down to twenty six to twenty eight inches of vacuum which is accomplished by looking at these two gages, now we are going to recharge the system. To do that we are going to open the valves, punch in the amount of refrigerant. This particular one is going to hold one point seven five pounds of freon. I'm going to program that in and press enter and then charge. At this point as you can see my gages are moving upwards indicating that the system is charging. Once the machine counts down to zero we close the service valves, the system is now charged and should be operational provided there are no mechanical defects in the system. Ok now that we've described how to recharge the system on the car I want to point out a few facts. To start with the air conditioner system is very dangerous. To start with if you cross the high side and the low side and try to recharge it you can get very seriously injured. The refrigerant which is a cold gas can spray back on you with the can exploding. A lot of bad things can happen with that, with gas burns over most of your body. With that being said the government has came out with several protocols governing automotive air conditioning. Number one is the Montreal protocol 609 which is a sanctioning agreement with the EPA that says that all certified techs must have the certification in order to legally service your car. And so I would highly recommend you leave your air conditioner servicing to a trained professional that is licensed and capable of performing this service.