Check Daytime Running Light System (Except For Wilderness Model)

Wiring diagram: 

Daytime running light system Ref. to WIRING SYSTEM>DAYTIME RUNNING LIGHT SYSTEM>WIRING DIAGRAM .

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK DTC  .
   1. Turn the ignition switch to ON.
   2. Read DTCs of the following items using the Subaru Select Monitor. Ref. to LAN SYSTEM (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .
      • [Body Control]
      • [Front Relay Control Module]

   Is DTC displayed?

   Yes:  Perform the diagnosis for the displayed DTCs.

   • [Body Control]: Ref. to BODY CONTROL (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC)>LIST .
   • [Front Relay Control Module]: Ref. to FRONT RELAY CONTROL MODULE (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC)>LIST .

   No:  Go to  2.

2. CHECK DATA MONITOR  .

   Using the Subaru Select Monitor, display the following items in the [Data monitor] of [Body Control]. Ref. to COMMON (DIAGNOSTICS)>DATA MONITOR .

   • [IGN voltage]
   • [Shift Position]
   • [EPB operating status]
   • [P SW]
   • [Lighting II Switch Input]

   Is the input signal normal?

   Yes:  Go to  3.

   No:  Check the defective part.

3. CHECK HARNESS  .
   1. Turn the ignition switch to OFF.
   2. Disconnect the front relay control module and headlight connector.
   3. Check the harness between the front relay control module and the headlight.

      Connector & terminal Headlight RH 

      (B68) No. 2 - (B121) No. 4:

      Headlight LH 

      (B69) No. 8 - (B122) No. 4:

   Is harness normal?

   Yes:  Go to  4.

   No:  Repair or replace the defective part.

4. CHECK HARNESS  .
   1. Disconnect the body integrated unit and headlight connector.
   2. Check the harness between the body integrated unit and headlight.

      Connector & terminal Headlight RH 

      (B121) No. 3 - (B72) No. 5:

      Headlight LH 

      (B122) No. 3 - (B72) No. 5:

   Is harness normal?

   Yes:  Go to  5.

   No:  Repair or replace the defective part.

5. 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.

      Connector & terminal Headlight RH 

      (B121) No. 4 (+) - (B121) No. 3 (-):

      Headlight LH 

      (B122) No. 4 (+) - (B122) No. 3 (-):

   Does the daytime running light illuminate?

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

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