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Home >> Subaru >> 2018 >> BRZ Limited, Automatic Trans >> Repair and Diagnosis >> Body & Frame >> Door Locks >> Entry Start System Entry System (Keyless Entry) >> Entry & Start System (Entry Function) >> Smart Unlock Operation Does Not Work From The Driver's Door (But Smart Lock Operation Works) >> Inspection steps
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Inspection steps

CAUTION:
  • Some functions of the entry & start system (entry function) use the LIN communication system and the CAN communication system. Refer to "HOW TO TROUBLESHOOT " (entry function). Inspect the communication function by referring to . Confirm that the communication system is functioning properly before proceeding to repair the entry & start system (entry function).
  • Before replacing the collation ECM (smart key ECM ASSY), refer to "entry & start system (entry function)". (Refer to ENTRY & START SYSTEM (ENTRY FUNCTION) )
  • Check if the electrical key transmitter SUB-ASSY is inside the vehicle.
  • After the repair work is complete, perform the "DTC output check operation" to confirm that the DTC is not output again.
  • Even if you want to check the entry lock operation several times, the setting does not allow you to perform the lock operation more than twice in a row. To perform the entry lock operation more than twice, you have to unlock a door once (you may use any type of unlock operation). This limitation applies only to the entry lock operation. A wireless lock or other types of lock operations can be performed any number of times without any limitations.
  1. Check the power door lock operation.
    1. Operate the door control switch on the power window regulator master switch ASSY, and check if the door locks or unlocks properly according to the switch operation you have performed. (Refer to OPERATION CHECK )

      Criteria: The door lock operation is performed properly.

      OK: Go to next step

      NG: Go to "Power door lock control system" ("Symptom table").

  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. Input the following menus: [Body Control] →[Data monitor]
    5. Based on the contents of the SSM4 display, read the [Data monitor].
      RANGE DESCRIPTION - MAIN BODY

      Tester display Measurement items/range Normal condition Notes for diagnosis
      [D Door Lock Pos] Driver's door unlock detection switch signal/Lock or Unlock [Lock]: The driver's door is locked.
      [Unlock]: The driver's door is unlocked.      		 -

      Criteria: On the SSM4 display, [LOCK] or [UNLOCK] is displayed as described in the table above.

      OK: Go to next step

      NG: Go to "Light system" (door unlock detection switch circuit).

  3. 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. Input the following menus: [Keyless Access(Collation ECM)] → [Data monitor]
    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
      [D seat unlock person sensor] Front door outer handle ASSY (driver's side) (unlock sensor)/[OFF] or [ON] [OFF]: The front door outer handle ASSY (driver's side) (unlock sensor) is not touched.
      [ON]: The front door outer handle ASSY (driver's side) (unlock sensor) is touched.      		  
      • This item displays whether the unlock sensor is ON or OFF (even when the sensor is properly touched [ON] is displayed only momentarily).
      • This item is displayed under [Data monitor]. When the entry unlock function does not work, use this item to check if the unlock sensor is faulty.

      Criteria: On the SSM4 display, [ON] or [OFF] is displayed as described in the table above.

      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 (smart key ECM ASSY) - front door outer handle ASSY).
    1. Disconnect the D41 and D48 collation ECM (smart key ECM ASSY) connectors.
    2. Disconnect the E1 front door outer handle ASSY connector.
    3. Measure the resistance according to the following table.

      Resistance

      Inspection terminals Inspection conditions Standard value
      D41-22 (SEN1) - E1-4 (SENS) Always 1 Ωor less
      D48-11 (GND) - Chassis ground Always 1 Ωor less
      D41-22 (SEN1) -chassis ground Always 10 kΩ or more

      OK: Go to next step

      NG: Repair or replace the harnesses or connectors.

  5. Inspect the front door outer handle ASSY (driver's door) unit.
    1. Reconnect the D41 and the D48 connectors of the collation ECM (smart key ECM ASSY).
    2. Reconnect the E1 front door outer handle ASSY (driver's door) connector.
    3. Using an oscilloscope, check the waveform.
      Fig 1: Waveform
      G12589313Courtesy of SUBARU OF AMERICA, INC.

      Criteria

      Inspection terminals Switch conditions Tool setting Specified condition
      D41-22 (SEN1) - D48-11 (GND) Procedure:
      1. The engine switch is OFF.
      2. The electrical key transmitter SUB-ASSY is outside the vehicle.
      3. All doors are locked.
      4. The electrical key transmitter SUB-ASSY is not in the appropriate range from the vehicle.
      5. Driver's door unlock sensor, not touched →touched
      		 2 V/DIV., 500 ms/DIV. Pulse generation (Refer to the waveform above)

      OK: Go to next step

      NG: Replace the front door outer handle ASSY (driver's door).

      Replacement of the collation ECM (smart key computer ASSY)

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