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 Shift Interlock System
The shift interlock system prevents shifting the transmission out of the PARK position unless the brake pedal is depressed. The shift interlock system consists of a shift lock actuator mounted on the ignition switch. The actuator is energized when the ignition switch is turned to RUN, locking the transmission range selector lever in the PARK position. When the brake pedal is applied and the brake pedal position (BPP) switch activated, the shift lock actuator is deactivated, allowing the selector lever to move out of the PARK position.
The ignition shift interlock cable locks the selector lever in the PARK position when the ignition switch is in the lock position. It also requires the selector lever to be in the PARK position in order to turn the ignition switch to the lock position.
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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