Brake lights (stoplights) are activated by a mechanical switch on the brake pedal.
To test a suspected bad stoplight switch, bypass it with a jumper wire. The stoplights should light when the wires are connected. Use the test light to see if there is power at one of the lights.
- If the lights come on when the wires are connected but not when the brakes are applied, replace the switch.
- If the stoplights operate without the key on, remove the stoplight fuse before removing the switch.
- If the new switch is adjustable, adjust it so that it is open when the pedal is released. The lights should come on about 1/4" after the pedal is applied.