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.
Shift Interlock Systems: Operation
Models with park lock cable, gearshift lever is locked in Park when ignition switch is in LOCK position. When ignition switch is turned to RUN position, gearshift lever is allowed movement to desired position. Ignition key cannot be removed until gearshift lever is returned to Park.
Models with shift interlock solenoid, gearshift lever cannot be moved from Park without simultaneously depressing brake pedal with ignition switch in RUN position. When pressure is applied to brake pedal, solenoid is actuated to release gearshift lever. Brake light switch completes or interrupts circuit to mechanically lock or unlock gearshift lever in Park by energizing or de-energizing solenoid, depending upon application. See WIRING DIAGRAMS .
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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