LEMON Manuals: Even more car manuals for everyone: 1960-2025
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) >> Interior Collation Is NG >> Inspection steps
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Inspection steps

CAUTION:
  • Some functions of the entry & start system (entry function) use the LIN communication system and the CAN communication system. Inspect the communication function 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 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) )
  • An antenna coil is present between the 2 terminals of the indoor electrical key antenna ASSY.
NOTE: Ensure that the entry cancel function (one of the customize setting available for the entry & start system) is not enabled. (Refer to CUSTOMIZE PARAMETERS )
  1. Check the entry & start system (entry function).
    1. Check if the entry lock/unlock function works properly. (Refer to OPERATION CHECK )

      Criteria: The entry lock/unlock function works properly.

      OK: Go to next step

      NG: Go to "Symptom table" (entry & start system (entry function)) (refer to NEITHER SMART LOCK NOR SMART UNLOCK OPERATION WORKS ON ANY OF THE DOORS (WIRELESS FUNCTION DOES NOT WORK EITHER) ).

  2. Check the entry & start system (start function).
    1. Remove the battery from the electrical key transmitter SUB-ASSY. (Refer to TRANSMITTER BATTERY (WITH SMART ENTRY) )
    2. Depress the brake pedal *1 or the clutch pedal *2, hold the electrical key transmitter SUB-ASSY near the engine switch, with its switch facing yourself.

      *1: With automatic transmission

      *2: With manual transmission

    3. Turn to IG ON, and check if the engine starts when you operate the engine switch.
      NOTE:
      • If the presence of the electrical key transmitter SUB-ASSY inside the detection area cannot be confirmed, remove the transmitter battery from the electrical key transmitter SUB-ASSY and then place the electrical key transmitter SUB-ASSY over the engine switch to check if the engine starts.
      • If the engine does not start during this inspection procedure, the collation ECM (smart key ECM ASSY), steering lock actuator ASSY (steering lock ECM), or the ID code box*1 might be faulty.

      *1: With ID code box

      Criteria: The engine starts.

      OK: Go to next step

      NG: Go to "Entry & start system" (start function) (refer to HOW TO PROCEED WITH TROUBLESHOOTING ).

      G10216224Courtesy of SUBARU OF AMERICA, INC.
  3. Checking the waveform environment
    1. Insert the transmitter battery into the electrical key transmitter SUB-ASSY (Refer to TRANSMITTER BATTERY (WITH SMART ENTRY) )
    2. Move the electrical key transmitter SUB-ASSY toward the indoor electrical key antenna ASSY no. 1 (front floor) and check if the engine starts.
      CAUTION: If the key is within 0.2 m (0.656 feet) of the indoor electrical key antenna ASSY no. 1 (front floor), communication may not be possible.
    3. Move the electrical key transmitter SUB-ASSY toward the indoor electrical key antenna ASSY no. 2 (rear floor) and check if the engine starts.

      If a setting other than [All] is specified for [Ignition Available Area] by customization, the engine does not start. Before proceeding with this inspection procedure, check that [All] is selected for this item. (Refer to CUSTOMIZE PARAMETERS )

      CAUTION: If the key is within 0.2 m (.0.656 feet) of the indoor electrical key antenna ASSY no. 2 (rear floor), communication is not possible.
      NOTE:
      • Try moving the electrical key transmitter SUB-ASSY closer to the door control receiver, so that it is less exposed to external radio waves. In this way, you can identify if the problem is caused by external radio waves or not.
      • If the failure occurs in certain locations or during certain periods of time, it may be due to interference from external radio waves. In addition, the vehicle can also be affected by external radio waves generated by components installed by a dealer. If such components are found, remove them before inspecting the vehicle.
      • Being close to a broadcast antenna, a large video display, a wireless garage door opener system, a wireless security camera, or a home security system makes the vehicle susceptible to interference from external radio waves. If this is the case, move the vehicle to another location to check if the problem improves.
      • If a tool for checking radio waves such as a signal-strength meter is available, take measurements in the LF band (which is used by the vehicle antenna to create a detection area) and the RF band (which is used by the electrical key transmitter SUB-ASSY for signal transmission) in the vicinity of the vehicle to check where the radio waves might be present.

      Criteria: The engine starts.

      OK: Go to next step

      NG: Go to Step 4.

      Interference from external radio waves

  4. 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. 1 (front floor):
        G12589328Courtesy of SUBARU OF AMERICA, INC.

        Check if the wireless door lock buzzer beeps when the electrical key transmitter SUB-ASSY is located at the inspection points.

    2. Check the indoor electrical key antenna ASSY no. 2 (rear floor).
      G12589329Courtesy of SUBARU OF AMERICA, INC.

      Check if the wireless door lock buzzer beeps when the electrical key transmitter SUB-ASSY is located at the inspection points.

      NOTE:
      • If the buzzer beeps, it means that the indoor transmitter is functioning properly.
      • You can identify which indoor electrical key antenna ASSY (front floor or rear floor) is functioning properly by checking if the buzzer beeps when the key is near the respective antennas.
      • If the buzzer does not go off when the key is near the indoor electrical key antenna ASSY, the circuit inside the collation ECM (smart key ECM ASSY) might be faulty.
      RESULT DESCRIPTION

      Result Go to
      Front side operation failure A
      Rear floor operation failure B
      Front and rear operation check results are OK. C
      1. Go to next step
      2. Go to Step 9.
      3. Replacement of the collation ECM (smart key computer ASSY)
  5. Check the harnesses and connectors (collation ECM (smart key ECM ASSY) - indoor electrical key antenna no. 1 (front floor)).
    1. Disconnect the D41 collation ECM (smart key ECM ASSY) connector.
    2. Disconnect the D26 indoor electrical key antenna ASSY no. 1 (front floor) connector.
    3. Measure the resistance according to the following table.

      Resistance

      Inspection terminals Inspection conditions Standard value
      D41-3 (CLG5) - D26-1 (ANTE5) Always 1 Ωor less
      D41-2 (CG5B) - D26-3 (CLGB) Always 1 Ωor less
      D41-3 (CLG5) - chassis ground Always 10 kΩ or more
      D41-2 (CG5B) - chassis ground Always 10 kΩ or more

      OK: Go to next step

      NG: Repair or replace the harnesses or connectors.

  6. Inspect the collation ECM (smart key ECM ASSY) (output to the electrical key antenna ASSY no. 1 (front floor)).
    1. Reconnect the D41 connector of the collation ECM (smart key ECM ASSY).
      Fig 1: Waveform
      G12589330Courtesy of SUBARU OF AMERICA, INC.
    2. Using an oscilloscope, check the waveform.

      Criteria

      Inspection terminals Conditions Tool setting Specified condition
      D26-1 (ANTE5) - D26-3 (CLGB) Procedure:
      1. The engine switch is OFF.
      2. A door is open.
      3. A door is closed.
      4. 30 seconds elapses.
      5. The electrical key transmitter SUB-ASSY is not inside the vehicle.
      		 2 V/DIV., 500 ms/DIV. Pulse generation (Refer to the waveform above)

      OK: Go to next step

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

  7. Replace the indoor electrical key antenna ASSY no. 1 (front floor).
    1. Temporarily replace the indoor electrical key antenna ASSY no. 1 (front floor) with a new one or one that functions normally.
  8. Perform the keyless access system check.
    1. Perform keyless access system check for the following antennas. (Refer to OPERATION CHECK )
    2. Check the indoor electrical key antenna ASSY no. 1 (front floor):
      G12589331Courtesy of SUBARU OF AMERICA, INC.

      Check if the wireless door lock buzzer beeps when the electrical key transmitter SUB-ASSY is located at the inspection points.

      Criteria: The wireless door lock buzzer beeps.

      OK: Go to next step

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

      END (indoor electrical key antenna ASSY no. 1 malfunction)

  9. Check the harnesses and connectors (collation ECM (smart key ECM ASSY) - indoor electrical key antenna ASSY no. 2).
    1. Disconnect the D40 collation ECM (smart key ECM ASSY) connector.
    2. Disconnect the H15 indoor electrical key antenna ASSY no. 2 (rear floor) connector.
    3. Measure the resistance according to the following table.

      Resistance

      Inspection terminals Inspection conditions Standard value
      D40-11 (CLG6) - H15-1 (ANTE6) Always 1 Ωor less
      D40-10 (CG6B) - H15-3 (CLGB) Always 1 Ωor less
      D40-11 (CLG6) - chassis ground Always 10 kΩ or more
      D40-10 (CG6B) - chassis ground Always 10 kΩ or more

      OK: Go to next step

      NG: Repair or replace the harnesses or connectors.

  10. Inspect the collation ECM (smart key ECM ASSY) (output to the indoor electrical key antenna no. 2).
    1. Reconnect the D40 collation ECM (smart key ECM ASSY) connector.
    2. Using an oscilloscope, check the waveform.
      Fig 2: Waveform
      G12589332Courtesy of SUBARU OF AMERICA, INC.

      Criteria

      Inspection terminals Conditions Tool setting Specified condition
      H15-1 (ANTE6) - H15-3 (CLGB) Procedure:
      1. The engine switch is OFF.
      2. A door is open.
      3. A door is closed.
      4. 30 seconds elapses.
      5. The electrical key transmitter SUB-ASSY is not inside the vehicle.
      		 2 V/DIV., 500 ms/DIV. Pulse generation (Refer to the waveform above)

      OK: Go to next step

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

  11. Replace the indoor electrical key antenna ASSY no. 2 (rear floor).
    1. Temporarily replace the indoor electrical key antenna ASSY no. 2 (rear floor) with a new one or one that functions normally.
  12. 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).
        G12589333Courtesy of SUBARU OF AMERICA, INC.

        Check if the wireless door lock buzzer beeps when the electrical key transmitter SUB-ASSY is located at the inspection points.

        Criteria: The wireless door lock buzzer beeps.

        OK: Go to next step

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

        END (indoor electrical key antenna ASSY no. 2 malfunction)

scientia non olet · About LEMON Manuals