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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-assembly 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 assembly). (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 SSM3.
    1. Connect the SSM3 to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn on the SSM3.
    4. Enter the following menu items: [Keyless access system check] →[Collation ECM] →[Unit customizing].
    5. Based on the contents of the SSM3 display, read the [Current Data Display & Save].

      Entry & Start

      ENTRY & START TESTER DISPLAY REFERENCE

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

      Result

      Result Go to
      The entry trunk open mode is ON. A
      The entry trunk open mode is OFF. B

      B: Specify the customize setting (go to "customize function") (Refer to CUSTOMIZE PARAMETERS  ).

      A: Go to next step

  2. Read numerical values using the SSM3.
    1. Connect the SSM3 to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn on the SSM3.
    4. Enter the following menu items: [Keyless access system check] →[Collation ECM] →[Unit customizing].
    5. Based on the contents of the SSM3 display, read the [Current Data Display & Save].

      Entry & Start

      ENTRY & START TESTER DISPLAY REFERENCE

      Tester display Measurement items/range Normal condition Notes for diagnosis
      [Tr/B-Door Unlock SW] Trunk opening switch assembly/[OFF] or [ON] ON: The trunk opening switch assembly is pressed.
      OFF: The trunk door opening switch assembly is not pressed.      		 -

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

      NG: Go to Step  8.

      OK: Go to next step

  3. Using the SSM3, execute [System Operation Check Mode].
    1. Connect the SSM3 to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn on the SSM3.
    4. Enter the following menu items: [Integ. unit mode] →[Work Support] →[System Operation Check Mode].
    5. Based on the contents of the SSM3 display, read the [Current Data Display & Save].

      Main body

      MAIN BODY ITEM DESCRIPTION

      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.

      NG: Go to Step  10.

      OK: Go to next step

  4. Checking the waveform environment
    1. Move the electrical key transmitter sub-assembly toward the electrical key antenna (trunk exterior antenna) and check the entry trunk open function.
      Fig 1: Checking Electrical Key Transmitter Sub-Assembly (Trunk Exterior Antenna)
      G10216287Courtesy of SUBARU OF AMERICA, INC.
      CAUTION: If the electrical key transmitter sub-assembly 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-assembly 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-assembly 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.

      NG: Go to Step 5.

      OK: 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 assembly no. 2 (rear floor).
      Fig 2: Checking Indoor Electrical Key Antenna Assembly No. 2 (Rear Floor)
      G10216288Courtesy of SUBARU OF AMERICA, INC.
    2. Hold the electrical key transmitter sub-assembly 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-assembly 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-assembly 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.

      NG: Go to Step 6.

      OK: Replacement of the collation ECM (smart key computer assembly)

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

      Resistance

      RESISTANCE REFERENCE

      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

      NG: Repair or replace the harnesses or connectors.

      OK: Go to next step

  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

      RESISTANCE REFERENCE

      Inspection terminals Inspection conditions Standard value
      1 (ANT1) - 2 (ANT2) Always 1 Ωor less
      Fig 3: Electrical Key Antenna Connector Terminal Identification
      G10216289Courtesy of SUBARU OF AMERICA, INC.

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

      OK: Replacement of the collation ECM (smart key computer assembly)

  8. Inspect the trunk opening switch assembly unit.
    1. Remove the trunk opening switch assembly. (Refer to TRUNK OPENING SWITCH ASSEMBLY )
    2. Inspect the trunk opening switch assembly. (Refer to INSTALLATION )

      NG: Replacement of the trunk opening switch assembly

      OK: Go to next step

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

      Resistance

      RESISTANCE REFERENCE

      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

      NG: Repair or replace the harnesses or connectors.

      OK: Replacement of the collation ECM (smart key computer assembly)

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

      NG: Replacement of the trunk lock assembly

      OK: Go to next step

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

      Resistance

      RESISTANCE REFERENCE

      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

      NG: Repair or replace the harnesses or connectors.

      OK: Go to next step

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

      Resistance

      RESISTANCE REFERENCE

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

      NG: Replacement of the instrument panel junction block assembly

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

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