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Headlight Control Switch Circuit

NOTE: If LEXUS scan tool is available, start test from step  1. If this scan tool is not available, start test from step  2.
  1. Using scan tool, check headlight control switch using DATA LIST. If headlight switch is faulty, go to next step. If headlight switch is okay, go to next test listed in appropriate SYMPTOM DIAGNOSIS table under TROUBLE SHOOTING .
  2. Check headlight control switch. See STEERING COLUMN SWITCHES article. Replace headlight control switch as necessary. Retest system operation. If headlight control switch is okay, go to next step.
  3. Check circuits for faults between headlight control switch and body control ECU No. 2. See WIRING DIAGRAMS . Repair or replace as necessary. If circuits are okay, go to next test listed in appropriate SYMPTOM DIAGNOSIS table under TROUBLE SHOOTING .
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