I don't know what the newer tours have in the way of a low fuel sensor. A previous car I had used a contact mounted on the same float sender/fuel pump array in the tank. When it touched it the light on the dash came on for "low fuel."
I would pull the tank unit first and play with it to see if the gas gauge moves. Put an ohm meter on the pins and see if it changes when you move the float. Maybe something is hanging it up. Easier and cheaper than pulling the dash apart and buying a gauge. Swap the fuel pump while you are in there. Some of the parts stores sell the whole unit for not much more than the pump. Hopefully someone else with the same year that had their pump out will remember the sender and know if it has a separate contact for the low fuel. If it does then something is stopping the float from dropping.
