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.
Key Lock
The key lock function is part of the security system. This function means that the key cannot be removed from the ignition switch (it cannot be turned from position I to 0) if the gear selector is not in the park (P) position. This applies only to vehicles with automatic transmissions.
This function is checked by the central electronic module (CEM). The start control module (SCU) contains a coil which is powered by the central electronic module (CEM). The central electronic module (CEM) receives a signal from the transmission control module (TCM) indicating the position of the gear selector. The key can be turned when the coil has been activated. The key cannot be turned if the coil is not activated.
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.