2000 Lexus SC 400FACTORY OEM SERVICE PROCEDURE

Master Switch Circuit

Disconnect master switch. Using DVOM, ensure continuity is present between ground and terminal No. 8 (White/Black wire) at master switch harness connector. Turn ignition on. Ensure battery voltage is present between ground and terminal No. 4 (Blue wire) at master switch harness connector. If circuit values are not as specified, repair circuits as necessary. See WIRING DIAGRAMSΒ .

Factory Service Tools

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:

  • 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.