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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. Check the entry function (entry trunk open function).
    1. Check if the entry trunk open function works properly. (Refer to OPERATION CHECK )
      RESULT DESCRIPTION

      Result Go to
      The entry trunk open function works properly. A
      The entry trunk open function does not work properly. B
      1. Go to next step
      2. Proceed to check other problems ("Symptom table") (refer to PROBLEM SYMPTOMS TABLE ).
  2. Checking the waveform environment
    1. Move the electrical key transmitter SUB-ASSY toward the indoor electrical key antenna ASSY no. 3 (trunk interior antenna) and check if the entry trunk compartment lock-in prevention function works.
      G12589339Courtesy of SUBARU OF AMERICA, INC.
      CAUTION: If the electrical key transmitter SUB-ASSY is within 0.2 m (0.656 feet) of the indoor electrical key antenna ASSY no. 3 (rear floor), communication is not possible.
      NOTE:
      • Try moving the electrical key transmitter SUB-ASSY closer to the indoor electrical key antenna ASSY no. 3 (trunk interior 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 electromagnetic interference.
      • 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 3.

      Interference from external radio waves

  3. Perform the keyless access system check.
    1. Perform keyless access system check for the following antennas. (Refer to OPERATION CHECK )
      G12589340Courtesy of SUBARU OF AMERICA, INC.
    2. Check if the wireless door lock buzzer beeps when the electrical key transmitter SUB-ASSY is located in the trunk.
      NOTE:
      • Place the key in the trunk.
      • If the buzzer beeps, it means that the indoor electrical key antenna ASSY no. 3 (located inside the trunk) is functioning properly. Criteria: The wireless door lock buzzer beeps.

      OK: Go to next step

      NG: Go to Step 4.

      Replacement of the collation ECM (smart key computer ASSY)

  4. Check the harnesses and connectors (collation ECM - indoor electrical key antenna no. 3).
    1. Disconnect the D40 collation ECM (smart key ECM ASSY) connector.
    2. Disconnect the H9 indoor electrical key antenna ASSY no. 3 (trunk interior antenna) connector.
    3. Measure the resistance according to the following table.

      Resistance

      Inspection terminals Inspection conditions Standard value
      D40-9 (CLG7) - H9-1 (ANTE7) Always 1 Ωor less
      D40-8 (CG7B) - H9-3 (CLGB) Always 1 Ωor less
      D40-9 (CLG7) - chassis ground Always 10 kΩ or more
      D40-8 (CG7B) - Chassis ground Always 10 kΩ or more

      OK: Go to next step

      NG: Repair or replace the harnesses or connectors.

  5. Check the collation ECM (smart key ECM ASSY).
    1. Connect the D40 collation ECM (smart key ECM ASSY) connector.
    2. Disconnect the H9 indoor electrical key antenna ASSY no. 3 (trunk interior antenna) connector.
    3. Measure the voltage according to the following table. Criteria
      Inspection terminals Switch conditions Tool setting Specified condition
      H9-1 (ANTE7) -H9-3 (CLGB) Procedure:
      1. The engine switch is OFF.
      2. The electrical key transmitter SUB-ASSY is not inside the vehicle.
      3. All doors are closed.
      4. Driver's door lock sensor, not touched →touched
      		 2 V/DIV., 500 ms/DIV. Pulse generation (Refer to the waveform below)
      G12589341Courtesy of SUBARU OF AMERICA, INC.

      OK: Go to next step

      NG: Replacement of the collation ECM (smart key computer ASSY)

  6. Replacement of the indoor electrical key antenna ASSY no. 3 (trunk interior antenna)
    1. Replace the indoor electrical key antenna ASSY no. 3 (trunk interior antenna). (Refer to ELECTRICAL OSCILLATOR KEY (FOR THE TRUNK ROOM) )
  7. Check the indoor electrical key antenna ASSY no. 3 (trunk interior antenna).
    1. Check if the entry trunk lock-in prevention function works properly.

      Criteria: The trunk lock-in prevention function works properly.

      OK: Go to next step

      NG: Replacement of the collation ECM (smart key computer ASSY)

      END (indoor electrical key antenna ASSY no. 3 malfunction)

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