Where do you add freon to the air conditioner on a 1989 Toyota SR5 Pickup?

To add freon to the air conditioner on a 1989 Toyota SR5 Pickup, locate the low-pressure service port, which is typically found on the larger diameter aluminum line running from the compressor to the evaporator. Remove the cap from the service port and connect the refrigerant can's hose to it. Make sure the engine is running and the AC is set to the maximum setting while you add freon. Always check the manufacturer's specifications for the correct type and amount of refrigerant.