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Check Halogen Headlight System

Trouble symptom: 

Headlight does not illuminate.

  1. CHECK HEADLIGHT AND TAIL LIGHT ILLUMINATION. 
    1. Turn the ignition switch to ON.
    2. Set the lighting switch to the switch 1 (TAIL/PARKING) and switch 2 (HEAD).

    Do the headlight and tail light illuminate?

    Yes  The headlight system is normal.

    No  Go to  2.

  2. CHECK BULB. 

    Check the headlight bulb.

    Is the bulb normal?

    Yes  Go to  3.

    No  Replace the headlight bulb.

  3. CHECK CURRENT DATA. 

    Display the data of «Lighting I Switch Input» and «Lighting II Switch Input» using Subaru Select Monitor.

    NOTE: For detailed operation procedures, refer to "Application help".

    Does the display switch between «OFF»←→«ON» when the lighting switch is moved from OFF position to the switch 1 (TAIL/PARKING) and switch 2 (HEAD) positions?

    Yes  Go to  6.

    No  Go to  4.

  4. CHECK COMBINATION SWITCH (LIGHT). 
    1. Turn the ignition switch to OFF.
    2. Check the combination switch (light). Refer to LIGHTING SYSTEM>COMBINATION SWITCH (LIGHT)>INSPECTION .

    Is the combination switch (light) normal?

    Yes  Go to  5.

    No  Replace the combination switch (light). Refer to LIGHTING SYSTEM>COMBINATION SWITCH (LIGHT) .

  5. CHECK HARNESS. 
    1. Disconnect the connectors of body integrated unit and combination switch (light).
    2. Check the harness between body integrated unit and combination switch (light).

    Is harness normal?

    Yes  Check the body integrated unit and replace it if defective.

    No  Repair or replace the harness.

  6. CHECK CURRENT DATA. 
    1. Turn the ignition switch to ON.
    2. Display the data of «Lighting I Lamp Output» and «Lighting II Lamp Output» using Subaru Select Monitor.

    Does the display switch between «OFF»←→«ON» when the lighting switch is moved from OFF position to the switch 1 (TAIL/PARKING) and switch 2 (HEAD) positions?

    Yes  Check the body integrated unit and replace it if defective.

    No  Go to  7.

  7. CHECK HARNESS. 
    1. Turn the ignition switch to OFF.
    2. Check the harness between body integrated unit and headlight and between body integrated unit and tail light.

    Is harness normal?

    Yes  Check the body integrated unit and replace it if defective.

    No  Repair or replace the harness.