BRAKELIGHT Switch
WARNING: This page is about a different car, the 2001 Mazda Protege, 2001 Mazda Millenia, 2001 Mazda MX-5 Miata, 2001 Mazda MPV, and 2001 Mazda 626. However, it is still accessible from the selected car via links, so may be relevant.
Disconnect brakelight switch connector. Using ohmmeter, check continuity between brakelight switch terminals. With brake pedal released, continuity should not be present. With brake pedal depressed, continuity should be present. If continuity is not as specified, replace brakelight switch.