KEY REMINDER WARNING SYSTEM Key Reminder Buzzer does not Sound

DESCRIPTION

The key reminder warning buzzer sounds when the driver door is opened while the ignition switch is off or ACC. The key reminder warning buzzer is activated when the main body ECU (multiplex network body ECU) sends an unlock warning switch signal and driver door courtesy light switch signal to the combination meter assembly via CAN communication.

WIRING DIAGRAM


  1. for LHD

    A018J21E01

  2. for RHD

    A018J21E02

CAUTION / NOTICE / HINT

Note


  • The key reminder warning system uses the CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting. Troubleshoot the key reminder warning system after confirming that the communication systems are functioning properly.

    Click here

  • As the door control battery is installed between the vehicle battery and main body ECU (multiplex network body ECU), first perform the inspections in On-Vehicle Inspection to confirm that there are no malfunctions in the power source circuit for the main body ECU (multiplex network body ECU) before performing this troubleshooting procedure.*

    Click here


    • *: for LHD

PROCEDURE


  1. CHECK COMBINATION METER ASSEMBLY (BUZZER OPERATION)


    1. Turn the ignition switch to ON. Place luggage on the front passenger seat to cause the seat belt warning light to blink.

    2. When driving the vehicle at 20 km/h (12 mph) or higher, check that the seat belt warning buzzer sounds to inform that the front passenger seat belt is not fastened.

      Tech Tips

      The key reminder warning system sounds the buzzer built into the combination meter assembly as a key reminder warning. This buzzer is also used for the seat belt warning system. Therefore, check the operation of the combination meter buzzer by checking if the buzzer sounds to inform that the seat belt is not fastened.

      OK
      Combination meter buzzer sounds.
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE COMBINATION METER ASSEMBLY Click here

    OK

  2. READ VALUE USING GTS (FR Door Courtesy SW, FL Door Courtesy SW)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / Main Body / Data List.

    5. Read the Data List according to the display on the GTS.


      Body Electrical > Main Body > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      FR Door Courtesy SW Front door courtesy light switch assembly (for RH) signal OFF or ON

      OFF: Front door RH closed

      ON: Front door RH open

      		 *1
      FL Door Courtesy SW Front door courtesy light switch assembly (for LH) signal OFF or ON

      OFF: Front door LH closed

      ON: Front door LH open

      		 *2

      • *1: for RHD

      • *2: for LHD


      Body Electrical > Main Body > Data List
      Tester Display
      FR Door Courtesy SW
      FL Door Courtesy SW
      OK
      The GTS indicates ON or OFF according to the driver door conditions shown in the table.
      Result
      Proceed to
      OK
      NG

    NG

    INSPECT FRONT DOOR COURTESY LIGHT SWITCH ASSEMBLY Click here

    OK

  3. READ VALUE USING GTS (Key Unlock Warning SW)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / Main Body / Data List.

    5. Read the Data List according to the display on the GTS.


      Body Electrical > Main Body > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Key Unlock Warning SW Unlock warning switch signal OFF or ON

      OFF: No key in ignition key cylinder

      ON: Key in ignition key cylinder

      		 -

      Body Electrical > Main Body > Data List
      Tester Display
      Key Unlock Warning SW
      OK
      The GTS indicates ON or OFF according to whether the key is in the ignition key cylinder.
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here

    NG

  4. INSPECT UNLOCK WARNING SWITCH ASSEMBLY


    1. Remove the unlock warning switch assembly.

      Click here

    2. Inspect the unlock warning switch assembly.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE UNLOCK WARNING SWITCH ASSEMBLY Click here

    OK

  5. CHECK HARNESS AND CONNECTOR (UNLOCK WARNING SWITCH ASSEMBLY - MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU))


    1. Disconnect the 4D instrument panel junction block assembly connector.

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      4D-28 - F52-1 (UN+) Always Below 1 Ω
      F52-2 (UN-) - Body ground Always Below 1 Ω
      F52-1 (UN+) or 4D-28 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY


    1. Remove the instrument panel junction block assembly.

      Click here

      A002AJYC06
      *a

      Component without harness connected

      (Instrument Panel Junction Block Assembly)

      		 - -

    2. Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      4D-28 - MB-3 (KSW) Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here

    NG

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here

  7. INSPECT FRONT DOOR COURTESY LIGHT SWITCH ASSEMBLY


    1. for LHD


      1. Remove the front door courtesy light switch assembly (for LH).

        Click here

      2. Inspect the front door courtesy light switch assembly (for LH).

        Click here

    2. for RHD


      1. Remove the front door courtesy light switch assembly (for RH).

        Click here

      2. Inspect the front door courtesy light switch assembly (for RH).

        Click here

      Result
      Result Proceed to
      OK A
      NG (for LHD) B
      NG (for RHD) C

    B

    REPLACE FRONT DOOR COURTESY LIGHT SWITCH ASSEMBLY (for LH) Click here

    C

    REPLACE FRONT DOOR COURTESY LIGHT SWITCH ASSEMBLY (for RH) Click here

    A

  8. CHECK HARNESS AND CONNECTOR (FRONT DOOR COURTESY LIGHT SWITCH ASSEMBLY - MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU))


    1. for LHD


      1. Disconnect the F19 main body ECU (multiplex network body ECU) connector.

      2. Measure the resistance according to the value(s) in the table below.

        Standard Resistance
        Tester Connection Condition Specified Condition
        M1-1 - F19-6 (FLCY) Always Below 1 Ω
        M1-1 or F19-6 (FLCY) - Body ground Always 10 kΩ or higher

    2. for RHD


      1. Disconnect the F19 main body ECU (multiplex network body ECU) connector.

      2. Measure the resistance according to the value(s) in the table below.

        Standard Resistance
        Tester Connection Condition Specified Condition
        L1-1 - F19-27 (FRCY) Always Below 1 Ω
        L1-1 or F19-27 (FRCY) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR