1997 Lexus SC 400FACTORY OEM SERVICE PROCEDURE

Test 19: Cruise Main Light Problem

Disconnect connector "D". Turn ignition on. Ground connector "D" terminal No. 3. If light bulb illuminates, repair open circuit between connector "D" terminal No. 3 and cruise ECU. If wiring is okay, replace cruise ECU. If bulb does not illuminate, check bulb. Replace as needed and retest. If bulb is okay, install a known good circuit plate and retest.

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.