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 Unlock Warning Switch Circuit
Turn ignition off and disconnect ATS ECU connector. Insert ignition key into ignition lock cylinder. Ensure continuity exists between ground and ECU connector terminal A20 (Light Green wire). If continuity is not present, repair open in unlock warning switch circuit. If continuity is present, remove key and ensure continuity is not present. If continuity is present, repair short in unlock warning switch circuit. If continuity is not present, replace ATS ECU and retest.
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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