Check Wiper Interlock Headlight System

Trouble symptom: 

The headlights do not go off when the wiper is deactivated, or the headlights do not turn on when the wiper is activated.

1. CHECK HEADLIGHT SYSTEM. 

   Check the operation of the headlight system. Is the headlight system normal?

   Yes:  Go to  2.

   No:  Check and repair the headlight system.

   • Halogen headlight: Refer to LIGHTING SYSTEM>HEADLIGHT SYSTEM>INSPECTION>CHECK HALOGEN HEADLIGHT SYSTEM .
   • LED headlight: Refer to LIGHTING SYSTEM>HEADLIGHT SYSTEM>INSPECTION>CHECK LED HEADLIGHT SYSTEM .
2. CHECK BODY INTEGRATED UNIT SETTING. 

   Display the data of «Illumination Sensor Setting» using Subaru Select Monitor.

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

   Is the setting «ON»?

   Yes:  Go to  3.

   No:  Turn the setting to «ON».

3. CHECK BODY INTEGRATED UNIT SETTING. 

   Display the data of «Wiper link Auto Light Setup» using Subaru Select Monitor. Is the setting «ON»?

   Yes:  Go to  4.

   No:  Turn the setting to «ON».

4. CHECK BODY INTEGRATED UNIT. 
   1. Display the data of «IGN voltage» using Subaru Select Monitor.
   2. Turn the ignition switch to ON.

   Is the voltage 10 - 15 V?

   Yes:  Go to  7.

   No:  Go to  5.

5. CHECK HARNESS. 

   Measure the voltage between F/B fuse No. 12 and chassis ground. Is the voltage 10 V or more?

   Yes:  Repair or replace the harness between the body integrated unit and the ignition switch.

   No:  Go to  6.

6. CHECK CONNECTOR. 

   Check the connector or terminal of the body integrated unit for poor contact. Is there any fault?

   Yes:  Repair or replace the connector and harness.

   No:  Check the body integrated unit and replace it if defective.

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

   Using the Subaru Select Monitor, display the data of «Lighting AUTO input».

   Does the display switch between «OFF»<↔>«ON» when the lighting switch is moved from OFF position to the AUTO position?

   Yes:  Go to  12.

   No:  Go to  8.

8. CHECK BODY INTEGRATED UNIT. 

   Measure the voltage between the body integrated unit connector and chassis ground.

   Connector & terminal 

   (B281) No. 16 (+) - Chassis ground (-):

   Does the voltage switch between OFF (9 to 16 V) <↔> ON (less than 1 V) when the lighting switch is moved from OFF position to the AUTO position?

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

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

   No:  Go to  9.

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

      Connector & terminal 

      (B71) No. 19 - (B281) No. 16:

   Is the resistance less than 10 Ω?

   Yes:  Go to  10.

   No:  Repair or replace the harness between the combination switch (light) and the body integrated unit.

10. CHECK HARNESS. 

    Check the harness between the combination switch (light) and chassis ground.

    Connector & terminal 

    (B71) No. 12 - Chassis ground:

    Is the resistance less than 10 Ω?

    Yes:  Go to  11.

    No:  Repair or replace the harness between the combination switch (light) and chassis ground.

11. CHECK COMBINATION SWITCH (LIGHT). 

    Check the combination switch (light). Refer to LIGHTING SYSTEM>COMBINATION SWITCH (LIGHT)>INSPECTION .

    Is the combination switch (light) normal when the combination switch (light) is moved to AUTO position?

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

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

    No:  Replace the combination switch (light).

12. CHECK BODY INTEGRATED UNIT. 

    Using the Subaru Select Monitor, display the data of «Fr wiper input».

    Does the display switch between «OFF»<↔>«ON» when the combination switch (wiper) is operated from OFF position to INT/LO/HI?

    Yes:  Go to  17.

    No:  Go to  13.

13. CHECK BODY INTEGRATED UNIT. 

    Measure the voltage between the body integrated unit connector and chassis ground.

    Connector & terminal 

    (B280) No. 2 (+) - Chassis ground (-):

    Does the voltage switch between OFF (less than 1 V) <↔> ON (9 to 16 V) when the combination switch (wiper) is operated to INT/LO/HI?

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

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

    No:  Go to  14.

14. CHECK HARNESS. 
    1. Disconnect the connectors of the front wiper motor and the body integrated unit.
    2. Check the harness between the front wiper motor and the body integrated unit.

       Connector & terminal 

       (B8) No. 1 - (B280) No. 2:

    Is the resistance less than 10 Ω?

    Yes:  Go to  15.

    No:  Repair or replace the harness between the front wiper motor and the body integrated unit.

15. CHECK HARNESS. 

    Check the harness between the front wiper motor and chassis ground.

    Connector & terminal 

    (B8) No. 4 - Chassis ground:

    Is the resistance less than 10 Ω?

    Yes:  Go to  16.

    No:  Repair or replace the harness between the he front wiper motor and chassis ground.

16. CHECK FRONT WIPER MOTOR. 

    Check the continuity between front wiper motor terminals.

    Connector & terminal 

    (B8) No. 3 - (B8) No. 5:

    Is there continuity?

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

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

    No:  Replace the front wiper motor. Refer to WIPER AND WASHER SYSTEMS>FRONT WIPER MOTOR AND LINK .

17. CHECK BODY INTEGRATED UNIT. 

    Using the Subaru Select Monitor, display the data of «Front washer switch input».

    Does the display switch between «OFF»<↔>«ON» when the front washer switch on the combination switch (wiper) is operated from OFF position?

    Yes:  Check the connection status of the harness and connector that may have a temporary poor contact.

    No:  Go to  18.

18. CHECK BODY INTEGRATED UNIT. 

    Measure the voltage between the body integrated unit connector and chassis ground.

    Connector & terminal 

    (B281) No. 32 (+) - Chassis ground (-):

    Does the voltage switch between OFF (9 to 16 V) <↔> ON (less than 1 V) when the front washer switch on the combination switch (wiper) is operated?

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

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

    No:  Go to  19.

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

       Connector & terminal 

       (B558) No. 3 - (B281) No. 32:

    Is the resistance less than 10 Ω?

    Yes:  Go to  20.

    No:  Repair or replace the harness between the combination switch (wiper) and the body integrated unit.

20. CHECK HARNESS. 

    Check the harness between the combination switch (wiper) and chassis ground.

    Connector & terminal 

    (B558) No. 2 - Chassis ground:

    Is the resistance less than 10 Ω?

    Yes:  Go to  21.

    No:  Repair or replace the harness between the combination switch (wiper) and chassis ground.

21. CHECK COMBINATION SWITCH (WIPER). 

    Check the continuity between terminals when the front washer switch on the combination switch (wiper) is pressed.

    Connector & terminal 

    (B558) No. 3 - (B558) No. 2:

    Is there continuity?

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

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

    No:  Replace the combination switch (wiper). Refer to WIPER AND WASHER SYSTEMS>COMBINATION SWITCH (WIPER) .