1998 Lexus SC 400FACTORY OEM SERVICE PROCEDURE

Door Open Detection Switch

NOTE: Door open detection switch is built into door lock motor assembly.

Remove door trim to access door lock assembly. Disconnect switch connector. Check continuity between terminal No. 3 (Red/White wire) and No. 6 (White/Black wire) with door open. Continuity should exist. Check continuity with door closed. Continuity should not exist. If continuity is not as specified, replace switch. If continuity is as specified, check wiring between switch, theft deterrent/door lock ECU and ground. See WIRING DIAGRAMSΒ . Repair as necessary.

Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.

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