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.
Stoplight Switch Circuit
Ensure stoplights operate when brake pedal is pressed. Leave ABS ECU connectors attached. Measure voltage between chassis ground and terminal B6 of ABS ECU connector. See Figure. If battery voltage is present, stoplight switch circuit is okay. If battery voltage is not present, check circuit between stoplight switch and ABS ECU. If circuit is okay, replace ABS ECU.
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.