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Home >> Subaru >> 2020 >> BRZ Limited, Automatic Trans >> Repair and Diagnosis >> External Pages >> Different car >> Section 26 (Entry Start System Start System (Keyless Start)) >> Entry & Start System (Start Function) >> The Power Does Not Turn On (Does Not Change To Both ACC ON Or IG ON) >> Inspection steps
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Inspection steps

WARNING: This page is about a different car, the 2018 Subaru BRZ. However, it is still accessible from the selected car via links, so may be relevant.
CAUTION:
  • Before performing troubleshooting that uses CAN communication of the entry & start system, perform the inspection in "How to troubleshoot", and check that there are no problems in the communication system. (Refer to HOW TO PROCEED WITH TROUBLESHOOTING )
  • Before replacing the collation ECM (smart key ECM ASSY), refer to "entry & start system (entry function)". (Refer to ENTRY & START SYSTEM (ENTRY FUNCTION) )
  • Check that no DTC is output. If any DTC is output, proceed to "List of diagnostic codes". (Refer to DIAGNOSTIC TROUBLE CODE CHART )
  • If the entry & start system has been disabled by the entry & start system customize settings, enable it before performing troubleshooting. (Refer to CUSTOMIZE PARAMETERS )
  • After finishing repair, check that the problem doesn't occur again.
  • Before performing the following inspection steps, check the fuses related to this system.
  1. Checking the wireless door lock control system (operation)
    1. Check that the wireless door lock function operates properly. (Refer to OPERATION CHECK )

      Criteria: The wireless door and lock function operates properly.

      OK: Go to next step

      NG: See "Entry & Start system" (The entry lock/unlock function and wireless function for all doors do not function) (Refer to NEITHER SMART LOCK NOR SMART UNLOCK OPERATION WORKS ON ANY OF THE DOORS (WIRELESS FUNCTION DOES NOT WORK EITHER) )

  2. Checking the harnesses and connectors (power supply) (Refer to DTC B2274 ACC CIRCUIT ABNORMAL )

    OK: Go to next step

    NG: Repair or replacement of the harnesses or connectors of the circuits that connect to the power source

  3. Checking the harnesses and connectors (GND) (Refer to DTC B2274 ACC CIRCUIT ABNORMAL )

    OK: Go to next step

    NG: Repair or replacement of the harnesses or connectors

  4. Checking the entry & start system
    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, and touch the logo side of the electrical key transmitter SUB-ASSY to the engine switch.

      *1: With automatic transmission

      *2: With manual transmission

    3. When you touch the logo side of the electrical key transmitter SUB-ASSY to the engine switch, check if the power mode changes.

      Criteria: The power mode changes.

      NOTE: If the power mode does not change, there is a problem in the cabin confirmation function.
      G10216224Courtesy of SUBARU OF AMERICA, INC.
      RESULT DESCRIPTION

      Result Go to
      NG (The power mode does not change) A
      OK (The power mode changes) B
      1. Go to next step
      2. Go to Step 13.
  5. Reading the values using the SSM4 (STOP LIGHT SWITCH 1, NEUTRAL SW/CLUTCH SW)
    1. With automatic transmission
      1. Connect the SSM4 to the DLC3.
      2. Turn the ignition switch to ON.
      3. Turn on the SSM4.
      4. Enter the following menus: [Keyless Access(Power Supply ECM)] →[Data monitor]
      5. Based on the contents of the SSM4 display, read the [Data monitor].
        RANGE DESCRIPTION - POWER SOURCE CONTROL

        Tester display Measurement items/range Normal condition Notes for diagnosis
        [Stop Light Switch 1] Brake pedal status/[OFF] or [ON] OFF: The brake pedal is not being depressed.
        ON: The brake pedal is being depressed.        		  
        • Using this item, determine if there is any problem with the stop light switch.
        • When this item is [OFF], the engine will not start.
        • If there is a problem caused by this item, if you press the engine switch for a certain amount of time, you can start the engine.

        Criteria: Based on the status of the stop light switch, "ON" (depressing the brake pedal) and "OFF" (your foot removed from the brake pedal) are displayed on the screen.

    2. With manual transmission
      1. Connect the SSM4 to the DLC3.
      2. Turn the ignition switch to ON.
      3. Turn on the SSM4.
      4. Enter the following menus: [Keyless Access(Power Supply ECM)] →[Data monitor]
      5. Based on the contents of the SSM4 display, read the [Data monitor].
        RANGE DESCRIPTION - POWER SOURCE CONTROL

        Tester display Measurement items/range Normal condition Notes for diagnosis
        [Neutral SW/Clutch SW] Clutch pedal status/[OFF] or [ON] OFF: The brake pedal is not being depressed.
        ON: The brake pedal is being depressed.        		  
        • Using this item, determine if there is any problem with clutch switch.
        • When this item is [OFF], the engine will not start.

        Criteria: Based on the status of the stop light switch, [ON] (depressing the clutch pedal) and [OFF] (your foot removed from the clutch pedal) are displayed on the screen.

        RESULT DESCRIPTION

        Result Go to
        OK A
        NG (with automatic transmission) B
        NG (with manual transmission) C
        1. Go to next step
        2. Go to Step 8.
        3. Go to Step 10.
  6. Reading the values using the SSM4 (POWER SUPPLY CONDITION)
    1. Connect the SSM4 to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn on the SSM4.
    4. Enter the following menus: [Keyless Access(Power Supply ECM)] →[Data monitor]
    5. Based on the contents of the SSM4 display, read the [Data monitor].
      RANGE DESCRIPTION - POWER SOURCE CONTROL

      Tester display Measurement items/range Normal condition Notes for diagnosis
      [Power supply status] Power supply status/[All OFF], [IG1 ON] or [ACC ON], [IG2 ON], [ST ON] [All OFF]: Engine switch off (ACC and IG)
      ACC ON: The engine switch is on (ACC).
      IG1 ON: The engine switch is on (IG) (IG1 relay on)
      IG2 ON: The engine switch is on (IG) (IG2 relay on)
      ST ON: The engine start request signal is sent.      		 Because [IG1 ON] and [IG2 ON] occur almost simultaneously, [IG1] may not be displayed ([IG1 ON] is displayed for a very short period of time).

      Criteria: Based on the change of power mode when you pressed the engine switch, the change contents are displayed.

      OK: Go to next step

      NG: Go to Step 12.

  7. Inspection of the collation ECM (smart key ECM ASSY)
    1. Connect the SSM4 to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn on the SSM4.
    4. Enter the following menus: [Keyless Access(Power Supply ECM)] →[Data monitor]
    5. Based on the contents of the SSM4 display, read the [Data monitor].
      RANGE DESCRIPTION - POWER SOURCE CONTROL

      Tester display Measurement items/range Normal condition Notes for diagnosis
      [Power supply status] Power supply status/[All OFF], [IG1 ON] or [ACC ON], [IG2 ON], [ST ON] [All OFF]: Engine switch off (ACC and IG)
      ACC ON: The engine switch is on (ACC).
      IG1 ON: The engine switch is on (IG) (IG1 relay on)
      IG2 ON: The engine switch is on (IG) (IG2 relay on)
      ST ON: The engine start request signal is sent.      		 Because [IG1 ON] and [IG2 ON] occur almost simultaneously, [IG1] may not be displayed ([IG1 ON] is displayed for a very short period of time).
    6. Measure the voltage according to the following table.
      G12589387Courtesy of SUBARU OF AMERICA, INC.

      Voltage

      STANDARD VALUE SPECIFICATION

      Inspection terminals Inspection conditions Standard value
      D41-6 (IG1D) - chassis ground IG OFF 1 V or less
      ACC ON 1 V or less
      IG ON 9V or more
      D48-9 (IG2D) - chassis ground IG OFF 1 V or less
      ACC ON 1 V or less
      IG ON 9V or more
      D41-4 (ACCD) - chassis ground IG OFF 1 V or less
      ACC ON 8.5V or more
      IG ON 8.5V or more

      OK: Go to next step

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

      Checking the circuits connected to the relay

  8. Unit inspection of the stop light switch ASSY
    1. Remove the stop light switch ASSY (Refer to REMOVAL )
    2. Inspect the stop light switch ASSY (Refer to UNIT INSPECTION )

      OK: Go to next step

      NG: Replacement of the stop light switch ASSY

  9. Checking the harnesses and connectors (collation ECM (smart key ECM ASSY) - stop light switch ASSY) (Refer to DTC B2285 STEERING LOCK POSITION SIGNAL ABNORMAL )

    OK: Go to next step

    NG: Repair or replacement of the harnesses or connectors

    Replacement of the collation ECM (smart key computer ASSY)

  10. Unit inspection of the clutch start switch ASSY
    1. Remove the clutch start switch ASSY (Refer to REMOVAL )
    2. Inspect the clutch start switch ASSY. (Refer to ON-VEHICLE INSPECTION )

      OK: Go to next step

      NG: Replacement of the clutch start switch ASSY

  11. Checking the harnesses and connectors
    1. Remove the D48 connector of the collation ECM (smart key ECM ASSY).
    2. Remove the A20 connector of the clutch start switch ASSY
    3. Measure the resistance according to the following table.
      STANDARD VALUE SPECIFICATION - RESISTANCE

      Tester display Inspection conditions Standard value
      D48-10 (CLUT) - A20-2 Always 1 Ω or less
      D48-10 (CLUT) - chassis ground Always 10 kΩ or more
    4. Reconnect the A20 connector of the clutch start switch ASSY
    5. Measure the voltage according to the following table.

      Voltage

      STANDARD VALUE SPECIFICATION

      Tester display Inspection conditions Standard value
      D48-10 (CLUT) -chassis ground Remove your foot from the clutch pedal →depress the clutch pedal 1V or less →9 V or more
      G12589388Courtesy of SUBARU OF AMERICA, INC.

      OK: Go to next step

      NG: Repair or replacement of the harnesses or connectors

      Replacement of the collation ECM (smart key computer ASSY)

  12. DTC check
    1. Check for DTC. (Refer to DTC CHECK/CLEAR )
      RESULT DESCRIPTION

      Result Go to
      No DTC is output A
      DTC B2784 is output B
      DTC B2785 is output C
      1. Go to next step
      2. Proceed to "List of diagnostic codes" (B2784) (Refer to appropriate service information )
      3. Proceed to "List of diagnostic codes" (B2785)

      Replacement of the electrical key transmitter SUB-ASSY

  13. Reading the values using the SSM4 (START SWITCH 1, 2)
    1. Connect the SSM4 to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn on the SSM4.
    4. Enter the following menus: [Keyless Access(Power Supply ECM)] →[Data monitor]
    5. Based on the contents of the SSM4 display, read the [Data monitor].
      RANGE DESCRIPTION - POWER SOURCE CONTROL

      Tester display Measurement items/range Normal condition Notes for diagnosis
      [System SW1] Connection status of the engine switch 1/[OFF] or [ON] OFF: The engine switch is not being pushed. ON: The engine switch is being pushed.  
      • If the engine switch is not pressed for a long enough time, the display contents may not change.
      • Using this item, determine if there is any problem with the engine switch input signal.
      [System SW2] Connection status of the engine switch 2/[OFF] or [ON] OFF: The engine switch is not being pushed. ON: The engine switch is being pushed.  
      • Back-up for engine switch 1. If you press the engine switch, the control function only works if the both engine switch 1 and 2 are operating properly.
      • Works in the same way as engine switch 1.

      Criteria: According to the engine switch operation, the [Data monitor] display contents are changed.

      RESULT DESCRIPTION

      Result Go to
      NG A
      OK B
      1. Go to next step
      2. Proceed to "Entry & Start system" (entry function) (ROOM OSCILLATOR does not recognize the key) (Refer to INTERIOR COLLATION IS NG )
  14. Unit inspection of the engine switch
    1. Remove the engine switch ASSY.
    2. Inspect the engine switch ASSY.

      OK: Go to next step

      NG: Replacement of the engine switch

  15. Checking the harnesses and connectors (collation ECM (smart key ECM ASSY) - engine switch)
    1. Remove the D41 connector of the collation ECM (smart key ECM ASSY).
    2. Remove the D25 connector of the engine switch.
    3. Measure the resistance according to the following table.
      STANDARD VALUE SPECIFICATION - RESISTANCE

      Tester display Inspection conditions Standard value
      D41-28 (SSW1) -D25-5 (SS1) Always 1 Ω or less
      D41-30 (SSW2) - D25-1 (SS2) Always 1 Ω or less
      D41-28 (SSW1) - chassis ground Always 10 kΩ or more
      D41-30 (SSW2) - chassis ground Always 10 kΩ or more

      OK: Go to next step

      NG: Repair or replacement of the harnesses or connectors

      Replacement of the collation ECM (smart key computer ASSY)

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