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Check Led Headlight System

Trouble symptom: 

Headlight does not illuminate, or headlight is weak.

  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 CURRENT DATA. 

    Display the data of [LED HEADLAMP (RH) error Signal] and [LED HEADLAMP (LH) error Signal] using Subaru Select Monitor. Ref. to OPERATION .

    Is [Turn_ON] displayed?

    Yes  : Go to  3.

    No  : Replace the headlight assembly.

  3. CHECK CONNECTOR CONNECTION. 

    Check that the headlight connector is connected.

    Is the connector connected?

    Yes  : Go to  6.

    No  : Connect the connector.

    When it does not illuminate even though the switch is turned to ON: Go to  6.

  4. CHECK FUSE. 
    1. Turn the ignition switch to OFF.
    2. Check the M/B fuses No. 6 and No. 7.

      Is the check result OK?

      Yes  Go to  6.

      No  Replace the defective fuse.

  5. CHECK HARNESS. 
    1. Disconnect the body integrated unit connector.
    2. Using the tester, measure the voltage between terminals.

      3. Connector & terminal 

      (B280) No. 3 (+) - Chassis ground (-):

      (B287) No. 3 (+) - Chassis ground (-):

      Is the voltage 8.5 - 16.5 V?

      Yes  Go to  6.

      No  Repair the harness between body integrated unit and fuse.

  6. CHECK HARNESS. 
    1. Disconnect the headlight connector.
    2. Turn the ignition switch to ON.
    3. Measure the voltage between the headlight connector and chassis ground.

      Connector and terminal. 

      RH side. 

      (B487) No. 1 (+) - Chassis ground (-):

      (B487) No. 2 (+) - Chassis ground (-):

      LH side. 

      (B477) No. 1 (+) - Chassis ground (-):

      (B477) No. 2 (+) - Chassis ground (-):

    Is the voltage 10 - 13.5 V?

    Yes  : Go to  7.

    No  : Go to  8.

  7. CHECK HEADLIGHT. 

    Apply battery voltage between headlight unit connector terminals.

    Terminals 

    Low beam. 

    No. 1 (+) - No. 4 (-):

    High beam. 

    No. 2 (+) - No. 4 (-):

    Does the headlight (low beam and high beam) come on at normal brightness?

    Yes  : Go to  8.

    No  : Replace the headlight. Ref. to LIGHTING SYSTEM>HEADLIGHT ASSEMBLY .

    Perform inspection for the malfunction signal line if the [LED HEADLAMP (RH) error Signal] and [LED HEADLAMP (LH) error Signal] do not illuminate in step 2). If short circuit to power supply occurs, repair or replace the harness.

  8. 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 switch 1 (TAIL/PARKING) and switch 2 (HEAD) positions?

    In addition, does the display of [Lighting Hi Lamp Output] switch between [OFF] ?? [ON] when the lighting switch is moved to the switch 2 (HEAD) position and the dimmer & passing switch to the switch UP position?

    Yes  : Go to  11.

    No  : Go to  9.

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

    Is the combination switch (light) normal?

    Yes  : Go to  10.

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

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

      Connector and terminal. 

      (i171) No. 35 - (i73) No. 18:

      (i171) No. 19 - (i73) No. 20:

      (i81) No. 28 - (i73) No. 20:

    Is harness normal?

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

    No  : Repair or replace the harness.

  11. 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. Ref. to OPERATION .

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

    In addition, does the display of [Lighting Hi Lamp Output] switch between [OFF] ?? [ON] when the lighting switch is moved to the switch 2 (HEAD) position and the dimmer & passing switch to the switch UP position?

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

    No  : Go to  12.

  12. CHECK HARNESS. 
    1. Turn the ignition switch to OFF.
    2. Disconnect the body integrated unit connector and the headlight and tail light connectors.
    3. Check the harness between body integrated unit and headlight and between body integrated unit and tail light.

      Connector and terminal. 

      Headlight RH

      (B280) No. 9 - (B487) No. 2:

      Headlight LH

      (B287) No. 7 - (B477) No. 2:

      Tail light RH

      (B280) No. 10 - (R266) No. 1:

      Tail light LH

      (B280) No. 10 - (R208) No. 1:

      Relay

      H/L LO relay No. 2 - (B287) No. 6:

      H/L LO relay No. 2 - (i171) No. 23:

      H/L LO relay No. 4 - (B281) No. 20:

      H/L LO relay No. 4 - (i171) No. 18:

    Is harness normal?

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

    No  : Repair or replace the harness.

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