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.
Theory Of Operation
When the Stop Lamp Switch is activated, a hardwired brake signal is sent to the Body Control Module (BCM). When the BCM receives this brake signal, indicating the Brake Pedal is applied, the BCM sends a voltage output through the Stop Lamp Driver circuits and Brake Signal 2 circuit to the Left and Right Tail Lamps, and the Center High Mounted Stop Lamp (CHMSL), which illuminates the Stop Lamps. A separate ground circuit for the Tail Lamps and CHMSL is provided through the wiring harness and is attached to the body sheet metal.
NO RELATED
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
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.