1996 Lexus SC 400FACTORY OEM SERVICE PROCEDURE

Key Unlock Warning Switch Circuit Test

Ensure key is not in ignition. Leave electrical connector attached to remote door lock ECU. Check voltage between chassis ground and terminal No. 6 of remote door lock ECU connector (backprobe the terminal). See Figure. If voltage is 10-14 volts, circuit is okay. If voltage is not 10-14 volts, repair wiring circuit between remote door lock ECU and key unlock warning switch.

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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