How do you program the Mazda 6 key fob to open the trunk?

To program the Mazda 6 key fob to open the trunk, first, sit in the driver's seat with all doors closed. Insert the key into the ignition and turn it to the "On" position without starting the engine. Press and hold the trunk release button on the key fob for a few seconds until you hear a confirmation sound. Turn the ignition back to the "Off" position to complete the programming.