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Inspection steps

CAUTION:
  • Some functions of the smart entry & start system (entry function) use the CAN communication system and the LIN communication system. Inspect the communication function first by referring to "How to troubleshoot" (refer to HOW TO PROCEED WITH TROUBLESHOOTING ). Confirm that the communication system is functioning properly before proceeding to repair the smart entry & start system (entry function).
  • Check if the electrical key transmitter SUB-ASSY is inside the vehicle.
  • Before proceeding with the inspection procedure, check that the DTC B1242 (wireless door lock control) is not output. (Refer to DTC CHECK/CLEAR )
  • Refer to the notes provided under "Smart entry & start system (entry function)" before proceeding to replace the collation ECM (smart key ECM ASSY). (Refer to ENTRY & START SYSTEM (ENTRY FUNCTION) )
  • After the repair work is complete, perform the "DTC output check operation" to confirm that the diagnostic code is not output again.
  1. Read numerical values using the SSM4.
    1. Connect the SSM4 to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn on the SSM4.
    4. Enter the following menu items: [Keyless Access(Collation ECM)] →[Customize]
    5. Based on the contents of the SSM4 display, read the [Data monitor].
      RANGE DESCRIPTION - ENTRY AND START

      Tester display Measurement items/range Normal condition Notes for diagnosis
      [Trunk Open Mode] Trunk opening switch ASSY/[OFF] or [ON] Customization status is displayed. -
      RESULT DESCRIPTION

      Result Go to
      The entry trunk open mode is ON. A
      The entry trunk open mode is OFF. B
      1. Go to next step
      2. Specify the customize setting (go to "customize function") (refer to CUSTOMIZE PARAMETERS ).
  2. Read numerical values using the SSM4.
    1. Connect the SSM4 to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn on the SSM4.
    4. Enter the following menu items: [Keyless Access(Collation ECM)] → [Customize]
    5. Based on the contents of the SSM4 display, read the [Data monitor].
      RANGE DESCRIPTION - ENTRY AND START

      Tester display Measurement items/range Normal condition Notes for diagnosis
      [Trunk lid/Rear gate unlock SW] Trunk opening switch ASSY/[OFF] or [ON] ON: The trunk opening switch ASSY is pressed. OFF: The trunk door opening switch ASSY is not pressed. -

      Criteria: The monitor changes as you operate the trunk opening switch ASSY

      OK: Go to next step

      NG: Go to Step 8.

  3. Using SSM4, perform an [Active Test].
    1. Connect the SSM4 to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn on the SSM4.
    4. Input the following menus: [Body Control] →[Active Test]
    5. Based on the contents of the SSM4 display, read the [Data monitor].
      RANGE DESCRIPTION - MAIN BODY

      Tester display Tested parts Control range Notes for diagnosis
      [Trunk and Back-Door Open] Operate the trunk lock motor. ON/OFF -

      Criteria: The trunk opens.

      OK: Go to next step

      NG: Go to Step 10.

  4. Checking the waveform environment
    1. Move the electrical key transmitter SUB-ASSY toward the electrical key antenna (trunk exterior antenna) and check the entry trunk open function.
      G12589335Courtesy of SUBARU OF AMERICA, INC.
      CAUTION: If the electrical key transmitter SUB-ASSY is within 0.2m of the rear bumper, communication is not possible.
      NOTE:
      • Press the switch located outside the trunk opener, holding the electrical key transmitter SUB-ASSY approximately 1 m above ground and approximately 0.3 m away from the vehicle, as shown in the figure.
      • Try moving the electrical key transmitter SUB-ASSY closer to the electrical key antenna (trunk exterior antenna), so that it is less likely to be affected by interference from external radio waves. In this way, you can identify if the problem is caused by external radio waves or not.
      • If the operation check reveals a normal result, it is highly likely that the problem is caused by the effect of electromagnetic interference. In addition, installing an additional component to the vehicle makes the vehicle more susceptible to interference from external radio waves. If such components are found, remove them, and then proceed to check the operation.

      Criteria: The entry function works properly.

      OK: Go to next step

      NG: Go to Step 5.

      Interference from external radio waves

  5. Perform the keyless access system check.
    1. Perform keyless access system check for the following antennas. (Refer to OPERATION CHECK )
      1. Check the indoor electrical key antenna ASSY no. 2 (rear floor).
        G12589336Courtesy of SUBARU OF AMERICA, INC.
    2. Hold the electrical key transmitter SUB-ASSY at the same level as the upper surface of the rear bumper, positioning it at the center of the rear end of the vehicle. Check if the wireless door lock buzzer beeps.
      NOTE:
      • Hold the electrical key transmitter SUB-ASSY at the same level as the upper surface of the rear bumper, positioning it at the center of the rear end of the vehicle (0.7 - 1.0 m (2.30 - 3.28 feet)). Check that the electrical key transmitter SUB-ASSY is facing in the same direction as shown in the figure.
      • If the buzzer beeps, it means that the transmitter located outside the trunk is functioning properly. Criteria: The wireless door lock buzzer beeps.

      OK: Go to next step

      NG: to Step 6.

      Replacement of the collation ECM (smart key computer ASSY)

  6. Check the harnesses and connectors (collation ECM - electrical key antenna).
    1. Disconnect the D40 collation ECM (smart key ECM ASSY) connector.
    2. Disconnect the H3 electrical key antenna (trunk exterior antenna) connector.
    3. Measure the resistance according to the following table.

      Resistance

      Inspection terminals Inspection conditions Standard value
      D40-1 (CG8B) - H3-2 (ANTE2) Always 1 Ωor less
      D40-2 (CLG8) - H3-1 (ANTE1) Always 1 Ωor less
      D40-1 (CG8B) - chassis ground Always 10 kΩ or more
      D40-2 (CLG8) - chassis ground Always 10 kΩ or more

      OK: Go to next step

      NG: Repair or replace the harnesses or connectors.

  7. Inspect the electrical key antenna (trunk exterior antenna) unit.
    1. Remove the electrical key antenna (trunk exterior antenna).
    2. Measure the resistance according to the following table.

      Resistance

      Inspection terminals Inspection conditions Standard value
      1 (ANTE8) - 2 (ANT2) Always 1 Ωor less
      G12589337Courtesy of SUBARU OF AMERICA, INC.

      OK: Go to next step

      NG: Replace the electrical key antenna (trunk exterior antenna).

      Replacement of the collation ECM (smart key computer ASSY)

  8. Inspect the trunk opening switch ASSY unit.
    1. Remove the trunk opening switch ASSY (Refer to REMOVAL )
    2. Inspect the trunk opening switch ASSY (Refer to UNIT INSPECTION )

      OK: Go to next step

      NG: Replacement of the trunk opening switch ASSY

  9. Check the harnesses and connectors (collation ECM - trunk opening switch ASSY).
    1. Disconnect the D40 collation ECM (smart key ECM ASSY) connector.
    2. Remove the J2 trunk opening switch ASSY connector.
    3. Measure the resistance according to the following table.

      Resistance

      Inspection terminals Inspection conditions Standard value
      D40-27 (TSW5) - J2-2 Always 1 Ωor less
      J2-1 - chassis ground Always 1 Ωor less
      D40-27 (TSW5) - chassis ground Always 10 kΩ or more

      OK: Go to next step

      NG: Repair or replace the harnesses or connectors.

      Replacement of the collation ECM (smart key computer ASSY)

  10. Inspect the trunk lock ASSY unit.
    1. Remove the trunk lock ASSY. (Refer to TRUNK PANEL LOCK ASSY )
    2. Inspect the trunk lock ASSY (Refer to UNIT INSPECTION )

      OK: Go to next step

      NG: Replacement of the trunk lock ASSY

  11. Check the harnesses and connectors (trunk lock - instrument panel junction block).
    1. Disconnect the 3B and 3D instrument panel junction block ASSY connectors.
    2. Disconnect the J3 trunk lock ASSY connector.
    3. Measure the resistance according to the following table.

      Resistance

      Inspection terminals Inspection conditions Standard value
      3B-6 - J3-1 Always 1 Ωor less
      3D-26 -J3-3 Always 1 Ωor less
      J3-2 - chassis ground Always 1 Ωor less
      3B-6 - chassis ground Always 10 kΩ or more
      3D-26 - chassis ground Always 10 kΩ or more

      OK: Go to next step

      NG: Repair or replace the harnesses or connectors.

  12. Inspect the instrument panel junction block ASSY unit.
    1. Remove the instrument panel junction block ASSY
    2. Remove the main body ECM (multiplex network body ECM) from the instrument panel junction block ASSY
    3. Measure the resistance according to the following table.

      Resistance

      Inspection terminals Conditions Specified condition
      3B-6 - MB-4 Always 1 Ωor less
      3D-26 - MB-12 Always 1 Ωor less

      OK: Go to next step

      NG: Replacement of the instrument panel junction block ASSY

      Replace the main body ECM (multiplex network body ECM).

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