How to Charge the AC in a Nissan Frontier

If non-refrigerated air comes out of the vent of your Nissan Frontier, you must recharge the refrigerant. There are two types of refrigerant used in automobiles. Vehicles manufactured before 1984 use R12 Freon. The United States Environmental Protection Agency has since phased out R12's usage. Newly manufactured vehicles use R134a. The process is the same across vehicle brands, so adding Freon to a Nissan Frontier is the the same as the process used in Chevrolets, Fords and other automobiles.

Park the car on flat ground. Guard against a rolling hazard by activating the Nissan's emergency brake.

Assemble your Freon recharging kit, if it was sold with the parts unattached. Attach the servicing hose and gauge to the can of Freon.

Open the Nissan's hood and find the air conditioning unit. Specifically, you are looking for two pressurized service connectors on a series of aluminum pipes. The higher side connector can be left alone, as it does not play a role in this task. Pull the cover off of the lower side connector and fit your Freon kit to it. Set the kit down in a stationary, safe place on top of the engine.

Open all of the Nissan's doors and then take a seat behind the steering wheel. Slide your key into the igntion and start the engine. Let the engine warm up.

Turn on the air conditioning unit and set it to the coolest temperature. Set the air conditioner's blower to its highest level.

Position a thermometer in the Nissan's central air conditioning duct.

Open the Freon canister by twisting the kit's handle all the way down. Let a minute's worth of Freon charge into the air conditioning unit's pipes.

Close the Freon canister by twisting the kit's handle up. This will give the Nissan Frontier's air conditioner a chance to evenly move the new Freon around the entire system. Continue to add Freon incrementally.

Monitor the thermometer in the air conditioning duct as you charge the system. The air temperature within the Nissan Frontier's air conditioning will drop during the charging process. When the system is fully charged, the thermometer will read 40 degrees. There is, however, one exception to consider. If you are outside during very hot weather, the thermometer my not read 40 degrees. In this case, the system's temperature will plateau somewhere between 40 and 60 degrees.

Remove the Freon recharging kit from the lower side connector. Let the new Freon circulate through the system for 10 minutes. Turn off the Nissan's air conditioner and engine to complete the process.