Toyota AC Pressure Specsby David McGuffinUpdated July 19, 2023
Your Toyota's air conditioning system is linked with a variety of components, hoses and fittings that circulate and pressurize refrigerant. All of these systems working together make cold air come out of your vents when the air conditioning system is turned on. Knowing the details surrounding a do-it-yourself refrigerant recharge will keep your air conditioning system from becoming over-pressurized.
If your Toyota's air conditioning refrigerant recharge kit is equipped with high- and low-pressure gauges, you can use them to help identify when your vehicle's refrigerant level is adequately pressurized. The low-pressure gauge should read between 25 and 40 psi (pounds per square inch). The high pressure gauge should read between 225 and 250 psi. To be safe, turn off the recharge kit's release valve as soon as the pressure reaches the lower extremes of adequate pressurization levels. If you put too much refrigerant in your system, you may cause refrigerant leaks.
In addition to using gauges, you can also use a thermometer placed on the dashboard air conditioning vents to test the coolness of the air coming out of your system during the recharge. When the air conditioning reaches between 40 and 50 degrees Fahrenheit, it is adequately pressurized. Nearly all commercially sold refrigerant recharge kits require that the automobile's engine is running and the air conditioner is turned on as part of the recharge process.
There is a specific amount of refrigerant that your Toyota has the capacity to hold. Most midsize cars made since 2000 will hold between 28 and 32 oz. of refrigerant; however, larger vehicles and those with rear air conditioning controls typically hold more refrigerant. Remember that you will most likely have some refrigerant left in your Toyota, so you will not be required to install the full capacity of refrigerant every time.
If the compressor is so low on refrigerant pressure that it won't turn on when the engine and air conditioning controls are on, then you will need to bypass the air conditioning pressure switch. Look for the single wire connector on the compressor's front side and connect it to a jumper wire. Attach the jumper wire to the Toyota's positive battery terminal. The compressor should turn on. However, you should already have the recharge kit attached to the low side fitting to prevent any damages that might happen to the compressor if it runs for too long without refrigerant or lubricant.
David McGuffin is a writer from Asheville, N.C. and began writing professionally in 2009. He has Bachelor of Arts degrees from the University of North Carolina, Asheville and Montreat College in history and music, and a Bachelor of Science in outdoor education. McGuffin is recognized as an Undergraduate Research Scholar for publishing original research on postmodern music theory and analysis.