The brake light switch is located on the side and activates the brake lights when the pedal is depressed. If there is voltage, check for power at the brake light wires at the tail light housings. If there is no power, repair the circuit between the switch and the brake lights. If there is power, check for bad ground using a jumper wire connected to a good ground. To replace the switch, remove the left side under the dash panel and the heater/air conditioning duct. Unplug the electrical connector from the switch and remove the clip that retains the switch and pushrod to the pin on the brake pedal arm. Slip the brake light switch off the pin and install the new switch by reversing the removal procedure.