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 "Help" of application.

   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?

   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). Ref. to LIGHTING SYSTEM>COMBINATION SWITCH (LIGHT)>INSPECTION .

   Is the combination switch (light) normal?

   Yes  : Go to  5.

   No  : Replace the 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).

      Connector and terminal. 

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

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

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

      (i171) No. 36 - (i73) No. 17:

      (i171) No. 26 - (i73) No. 11:

   Is harness normal?

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

   • Inspection: Ref. to BODY CONTROL (DIAGNOSTICS)>BASIC DIAGNOSTIC PROCEDURE .
   • Replacement: Ref. to SECURITY AND LOCKS>BODY INTEGRATED UNIT .

   No  : Repair or replace the harness.

6. CHECK CURRENT DATA. 
   1. Turn the ignition switch to ON.
   2. Display the data of [Lighting I Switch Input] and [Lighting II Switch Input] 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?

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

   • Inspection: Ref. to BODY CONTROL (DIAGNOSTICS)>BASIC DIAGNOSTIC PROCEDURE .
   • Replacement: Ref. to SECURITY AND LOCKS>BODY INTEGRATED UNIT .

   No  : Go to  9.

7. 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  8.

   No:  Replace the defective fuse.

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

      Connector & terminal 

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

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

      Is the voltage 8.5 - 16.5 V?

      Yes:  Go to  9.

      No:  Repair the harness between body integrated unit and fuse.

9. 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.

      Connector and terminal. 

      Headlight RH

      (B280) No. 9 - (B487) No. 5:

      Headlight LH

      (B287) No. 7 - (B477) No. 5:

      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.

   • Inspection: Ref. to BODY CONTROL (DIAGNOSTICS)>BASIC DIAGNOSTIC PROCEDURE .
   • Replacement: Ref. to SECURITY AND LOCKS>BODY INTEGRATED UNIT .

   No  : Repair or replace the harness.