Abstract: A tire deflation monitor and method of making the same including a pressure switch consisting of a cup-shaped conducting retainer element and a cup-shaped substantially rigid electrical conducting diaphragm that has a very short travel. The diaphragm closes against a conducting base member spaced very close to the diaphragm but separated therefrom only by a thin insulator so that the contact travel of the diaphragm is very short and the switch is very insensitive to temperature gradients. A first terminal is connected to the diaphragm and a second terminal is connected to the base member. The retainer is roll staked around the diaphragm and the conducting base member.