Abstract: A device which facilitates the testing of pressure switches included in the brake systems of locomotives. An air line is tapped into the pressure line of each switch and is provided with a quick connect coupling conveniently located on a test panel. Another quick connect coupling on the panel connects with the main air reservoir of the brake system. Also located on the test panel adjacent to the respective couplings are pairs of electrical receptacles for each switch. The receptacles connect with electrical conductors which lead to opposite sides of each switch contact. A preselected test pressure may be applied to each switch by connecting an air hose equipped with an adjustable reducing valve and pressure gauge between the main air reservoir coupling and the coupling for the switch to be tested. An ohmmeter may be connected across the receptacles for the switch contact under test to indicate whether the switch contact is open or closed at the test pressure.