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Test No. 8

NOTE: Headlight relay will be on by operating the headlight switch. The transistor that activates headlight relay may be operated by headlight switch for a fail-safe feature, or by instrument panel Electronic Control Unit (ECU). Instrument panel ECU will prevent headlights from turning off if a problem exists in the automatic light control system.

  1. Check Headlight Relay

    Check operation of headlight relay. See HEADLIGHT RELAY  under COMPONENT TESTS. If headlight relay operates properly, go to next step. If headlight relay is defective, replace headlight relay.

  2. Check Headlight Relay Wiring

    Check for defective connectors and wiring between battery, headlight relay and instrument panel ECU. See WIRING DIAGRAMS . Instrument panel ECU is located behind center of instrument panel and contains a 14-pin, 18-pin and 22-pin electrical connector. See Figure.
  3. If connectors and wiring are okay, go to the next test listed. See appropriate TROUBLE SHOOTING SYMPTOMS table under TROUBLE SHOOTING . If connectors or wiring are defective, repair as necessary.
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