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Headlight Relay 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. Check Headlight Relay Using Scan Tool

    Using scan tool, operate headlight relay in ACTIVE TEST. If headlight relay does not operate (headlights do not illuminate), go to next step. If headlight relay operates (headlights illuminate), go to next test listed in appropriate TROUBLE SHOOTING SYMPTOMS table.

  2. Check Headlight Relay

    Check headlight relay. See HEADLIGHT RELAY under COMPONENT TESTS. If headlight relay is okay, go to next step. Replace headlight relay as necessary. Retest system operation.

  3. Check Circuits

    Check circuits for faults between headlight relay, body control ECU and battery. See WIRING DIAGRAMS. Repair or replace as necessary. If circuits are okay, go to next test listed in appropriate TROUBLE SHOOTING SYMPTOMS table.
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