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Daytime Running Light Module Check

  1. CHECK FUSE  .
    1. Turn the ignition switch to OFF.
    2. Check the fuse on the upstream of the daytime running light relay.

      Is the fuse OK?

      Yes  : Go to  2 .

      No  : Replace the fuse.

  2. CHECK RELAY  .

    Check the daytime running light relay. Ref. to LIGHTING SYSTEM>RELAY AND FUSE>INSPECTION .

    Is the relay OK?

    Yes  : Go to  3 .

    No  : Replace the relay.

  3. CHECK BODY INTEGRATED UNIT  .

    Using the Subaru Select Monitor, read DTC of [Body Control]. Ref. to BODY CONTROL (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

    Is DTC displayed?

    Yes  : Perform the diagnosis according to the DTC. Ref. to BODY CONTROL (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC)>OPERATION .

    No  : Go to  4 .

  4. CHECK CURRENT DATA  .

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

    • [EPB operating status]
    • [Shift Position]
    • [Lighting II Switch Input]
    • [P SW]
    • [Power Supply Voltage]

    Is the input signal normal?

    Yes  : Go to  5 .

    No  : Check the defective part.

  5. CHECK CURRENT DATA  .
    1. Start the engine.
    2. Release the parking brake and place the shift position to other than "P" range.
    3. Display the [Daytime Running Light(Alternate System) Output] data using Subaru Select Monitor. Ref. to BODY CONTROL (DIAGNOSTICS)>DATA MONITOR .

      Does the display of [Daytime Running Light(Alternate System) Output] switch between [OFF] ←→ [ON] when the lighting switch is switched from the OFF position to the II (HEAD) position?

      Yes  : Go to  6 .

      No  : Replace the body integrated unit. Ref. to BODY CONTROL/COMMUNICATION SYSTEM>BODY INTEGRATED UNIT .

  6. CHECK DAYTIME RUNNING LIGHT ILLUMINATION  .
    1. Disconnect the headlight connector.
    2. Apply battery voltage to the DRL terminal input of the headlight unit.
      CAUTION: When applying battery voltage, do not mix up the positive (+) side and the negative (-) side. Incorrect polarity connection may cause internal LED damage.

      Terminals 

      NO.

      3 (+) - NO. 15 (-):

      Does the daytime running light illuminate?

      Yes  : Go to  7 .

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

  7. CHECK HARNESS  .
    1. Disconnect the connectors of body integrated unit, daytime running light relay and headlight.
    2. Check each harness.

      Connector and terminal 

      (B121) No. 3 - Daytime running light relay No. 3:

      (B122) No. 3 - Daytime running light relay No. 3:

      (B72) No. 5 - Daytime running light relay No. 4:

      Is harness normal?

      Yes  : Replace the body integrated unit. Ref. to BODY CONTROL/COMMUNICATION SYSTEM>BODY INTEGRATED UNIT .

      No  : Repair or replace the harness.