Where is the low pressure air conditioner port on a 2004 Toyota Sienna?

On a 2004 Toyota Sienna, the low pressure air conditioning service port is located on the larger diameter aluminum line, typically near the firewall on the passenger side of the engine compartment. It is usually covered with a blue or black cap. To access it easily, you may need to remove any obstructions in the area, such as engine covers or other components. Always ensure the engine is off before attempting to service the AC system.