Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Brake Light Switch
The purpose of the brake light switch is to provide the engine control module (ECM) with information indicating whether the brake pedal is depressed.
When the brake pedal is pressed down, a signal is sent to the Engine control module (ECM), which turns off the cruise control (if it is activated). The brake pedal position sensor also handles the function for switching off cruise control.
The brake light switch is supplied with power from the ignition switch (terminal 30). When the brake pedal is depressed the switch closes and a high signal (12 V) is transmitted to the engine control module (ECM).
The stop lamp switch can be diagnosed by the engine control module (ECM) and its status (depressed or not) can be read off.
The brake light switch is on the pedal box by the brake pedal.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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