FixVault

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. Ref. to LIGHTING SYSTEM>HEADLIGHT SYSTEM>INSPECTION>CHECK HEADLIGHT SYSTEM .

  2. CHECK BODY INTEGRATED UNIT SETTING  .

    Display the data of [Illumination Sensor Setting] and [Wiper Link Auto Light Setup] using Subaru Select Monitor. Ref. to BODY CONTROL (DIAGNOSTICS)>CUSTOMIZE .

    Is the setting in the [Support] and [ON]?

    YES  : Go to  3.

    NO  : Turn the setting to [Support] and [ON].

  3. CHECK BODY INTEGRATED UNIT  .
    1. Display the [IGN voltage] data using Subaru Select Monitor. Ref. to BODY CONTROL (DIAGNOSTICS)>DATA MONITOR .
    2. Turn the ignition switch to ON.

    Is the voltage 10 - 15 V?

    YES  : Go to  6.

    NO  : Go to  4.

  4. CHECK HARNESS  .

    Measure the voltage between F/B fuse No. 5 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  5.

  5. 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.

  6. CHECK BODY INTEGRATED UNIT  .

    Display the following items using Subaru Select Monitor. Ref. to BODY CONTROL (DIAGNOSTICS)>DATA MONITOR .

    • Except for C5
      • [Lighting AUTO input]
    • For C5
      • [Lighting OFF Switch Input]
    • Does the display change as [OFF] ←→ [ON] when the lighting switch is moved from the OFF position to the AUTO position? (Except for C5)
    • Does the display change as [OFF] ←→ [ON] when the lighting switch is moved from the AUTO position to the OFF position? (For C5)

    YES  : Go to  11.

    NO  : Go to  7.

  7. CHECK BODY INTEGRATED UNIT  .

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

    Connector & terminal 

    (i81) No. 20 (+) - Chassis ground (-):

    • Does the voltage change as OFF (9 to 16 V) ←→ ON (less than 1 V) when the lighting switch is moved from the OFF position to the AUTO position? (Except for C5)
    • Does the voltage change as OFF (9 to 16 V) ←→ ON (less than 1 V) when the lighting switch is moved from the AUTO position to the OFF position? (For C5)

    YES  : Go to  8.

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

  8. 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 

    Except for C5

    (i73) No. 19 - (i81) No. 20:

    For C5

    (i73) No. 18 - (i81) No. 20:

    Is the resistance less than 10 Ω?

    YES  : Go to  9.

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

  9. CHECK HARNESS  .

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

    Connector & terminal 

    (i73) No. 12 - Chassis ground:

    Is the resistance less than 10 Ω?

    YES  : Go to  10.

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

  10. CHECK COMBINATION SWITCH (LIGHT)  .

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

    • Is the combination switch (light) normal when the combination switch (light) is moved to AUTO position? (Except for C5)
    • Is the combination switch (light) normal when the combination switch (light) is moved from AUTO position to OFF position? (For C5)

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

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

  11. CHECK BODY INTEGRATED UNIT  .

    Display the [Fr wiper input] data using Subaru Select Monitor. Ref. to BODY CONTROL (DIAGNOSTICS)>DATA MONITOR .

    Does the display switch between [OFF] ←→ [ON] when the combination switch (wiper) is operated from OFF position to INT/LO/HI position?

    YES  : Go to  16.

    NO  : Go to  12.

  12. CHECK BODY INTEGRATED UNIT  .

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

    Connector & terminal 

    (B280) No. 6 (+) - Chassis ground (-):

    Does the voltage switch between OFF (less than 1 V) ←→ ON (9 to 16 V) when the combination switch (wiper) is operated from OFF position to INT/LO/HI position?

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

    NO  : Go to  13.

  13. 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. 6:

    Is the resistance less than 10 Ω?

    YES  : Go to  14.

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

  14. 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  15.

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

  15. 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.

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

  16. CHECK BODY INTEGRATED UNIT  .

    Display the [Front washer switch input] data using Subaru Select Monitor. Ref. to BODY CONTROL (DIAGNOSTICS)>DATA MONITOR .

    Does the display switch between [OFF] ←→ [ON] when the front washer switch on the combination switch (wiper) is operated from the OFF position?

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

    NO  : Go to  17.

  17. CHECK BODY INTEGRATED UNIT  .

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

    Connector & terminal 

    (i81) No. 12 (+) - Chassis ground (-):

    Does the voltage switch between OFF (less than 1 V) ←→ ON (9 to 16 V) when the front washer switch on the combination switch (wiper) is operated from the OFF position?

    YES  :

    Check the body integrated unit and replace it if defective.

    NO  : Go to  18.

  18. 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 

    (i68) No. 3 - (i81) No. 12:

    Is the resistance less than 10 Ω?

    YES  : Go to  19.

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

  19. CHECK HARNESS  .

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

    Connector & terminal 

    (i68) No. 2 - Chassis ground:

    Is the resistance less than 10 Ω?

    YES  : Go to  20.

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

  20. CHECK COMBINATION SWITCH (WIPER)  .

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

    Connector & terminal 

    (i68) No. 3 - (i68) No. 2:

    Is there continuity?

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

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