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DTC B2575: ALC Headlight System Fault: Testing

  1. If body function controller (BFC) diagnostic system check has been performed, go to next step. If body function controller (BFC) diagnostic system check has not been performed, go toBODY FUNCTION CONTROLLER (BFC) DIAGNOSTIC SYSTEM CHECK  under SYSTEM TESTS.
  2. If no other ALC DTCs exist, go to next step. If any other ALC DTCs exist, repair those DTCs first.
  3. Turn low beam headlights on. If both low beam headlights illuminate, go to next step. If both low beam headlights do not illuminate, go to step  7 .
  4. Using scan tool, read BFC INPUT for LOW BEAM/DRL FEEDBACK. If scan tool displays DRL ON, go to next step. If scan tool does not display DRL ON, go to step  7 .
  5. Turn high beam headlights on. If both high beam headlights illuminate, go to next step. If both high beam headlights do not illuminate, go to step  7 .
  6. Using scan tool, read BFC INPUT for HIGH BEAM FEEDBACK. If scan tool displays HIGH BEAMS ON, go to step  8 . If scan tool does not display HIGH BEAMS ON, go to next step.
  7. Locate problem in headlight and DRL system. See appropriate wiring diagram in HEADLIGHT SYSTEMS & DAYTIME RUNNING LIGHTS article. If repair is made to DRL system, go to step  9 . If repair is not made to DRL system, go to next step.
  8. Replace BFC. See BODY FUNCTION CONTROLLER (BFC)  under REMOVAL & INSTALLATION. After repairs, go to next step.
  9. Reconnect all disconnected components and connectors. Clear DTCs. Perform BODY FUNCTION CONTROLLER (BFC) DIAGNOSTIC SYSTEM CHECK  under SYSTEM TESTS.
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