1993 Lexus SC 400FACTORY OEM SERVICE PROCEDURE

Door Open Detection Switch Circuit Test

  1. Door open detection switch comes on when door is opened. Battery voltage is applied to remote door lock ECU when all doors are closed (door open detection switch for all doors are off). Ensure door open warning light comes on when each door is opened and goes off when each door is closed. If warning light does not operate as described, repair appropriate courtesy switch circuit.
  2. Gain access to remote door lock ECU. Turn remote door lock main switch to ON position. Using a DVOM, measure voltage between ground and ECU terminal No. 10. See Figure. Voltage should be 10-14 volts.
  3. If voltage is as specified, circuit is okay. If voltage is not as specified, check and repair wiring circuit(s) between remote door lock ECU and door open detection switch as necessary.
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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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