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
1998 Lexus SC 300SECTION Key Unlock Warning Switch Circuit
- Disconnect ignition switch connector. Connect ohmmeter between terminals No. 9 and 10. See Fig 1. With key inserted into ignition switch, continuity should exist. With key removed from ignition switch, continuity should not exist.
- If continuity is not as specified, replace key unlock warning switch. If continuity is as specified, check for faulty wiring between theft deterrent/door lock ECU and key unlock warning switch, and between key unlock warning switch and ground. See WIRING DIAGRAMS . If no faults are found in wiring, circuit is okay. Proceed to next test listed in TROUBLE SHOOTING .
RENDER: 1.0x
NO RELATED
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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.