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Power Source Mode does not Change to ON (IG and ACC) [08/2019 - ]: Procedure

  1. CHECK ELECTRICAL KEY TRANSMITTER SUB-ASSEMBLY 
    1. Press a switch of the electrical key transmitter sub-assembly.

      OK

      The electrical key transmitter sub-assembly LED illuminates.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  12

    Result: 

    OK 

    See step  2

  2. READ VALUE USING TECHSTREAM (KEY LOW BATTERY) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Smart Key / Data List.
    5. Read the Data List according to the display on the Techstream.
      BODY ELECTRICAL > SMART KEY > DATA LIST

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Key Low Battery Transmitter battery depleted No or Yes No: Transmitter battery not depleted
      Yes: Transmitter battery depleted      		 The electrical key transmitter sub-assembly sends voltage information to the certification ECU (smart key ECU assembly) when it is transmitting. The certification ECU (smart key ECU assembly) displays "Yes" for the "Key Low Battery" item of the Data List when this voltage information indicates 2.2 V or less. This Data List item should be checked when the electrical key transmitter sub-assembly is at room temperature (example: at -20°C (-4°F), "Yes" may be displayed even if the transmitter battery is new).

      OK

      "No" is displayed on the Techstream screen.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE TRANSMITTER BATTERY. Refer to  REPLACEMENT [08/2019 - ] 

    Result: 

    OK 

    See step  3

  3. CHECK POWER SOURCE MODE 
    1. Get into the vehicle while carrying an electrical key transmitter sub-assembly.
    2. Move the shift lever to P.
    3. Press the engine switch with the brake pedal released and check that the power source mode changes.

      Result

      Result Proceed to
      The power source mode changes A
      The power source mode does not change B

    Result: 

    A 

    END (AFFECTED BY WAVE INTERFERENCE) 

    Result: 

    B 

    See step  4

  4. CHECK SMART KEY SYSTEM (for Start Function) 
    1. Remove the transmitter battery from the electrical key transmitter sub-assembly.
    2. With the brake pedal depressed, hold the electrical key transmitter sub-assembly near the engine switch and check if the power source mode changes.

      OK

      The power source mode changes.

      HINT: 

      If the power source mode changes, the cabin verification is malfunctioning.

      GTY914026Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 Engine Switch
      *2 Electrical Key Transmitter Sub-assembly

      Result

      Result Proceed to
      The power source mode does not change A
      The power source mode changes B

    Result: 

    B 

    See step  11

    Result: 

    A 

    See step  5

  5. CHECK FOR DTC 
    1. Using the Techstream, check for certification ECU (smart key ECU assembly) DTCs.

      Refer to DTC CHECK / CLEAR [08/2019 - ]

      Result

      Result Proceed to
      DTCs are not output A
      Smart key system (for Start Function) DTCs are output B

    Result: 

    B 

    GO TO DIAGNOSTIC TROUBLE CODE CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART [08/2019 - 08/2021]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [08/2021 - 08/2022]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [08/2022 - ] 

    Result: 

    A 

    See step  6

  6. CHECK HARNESS AND CONNECTOR (POWER SOURCE) 

    See step  1

    Result

    Proceed to
    OK
    NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR IN CIRCUIT CONNECTED TO POWER SOURCE 

    Result: 

    OK 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (GROUND) 

    See step  2

    Result

    Proceed to
    OK
    NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  8

  8. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - DRIVER SIDE JUNCTION BLOCK ASSEMBLY) 
    1. Disconnect the F113 and F114 certification ECU (smart key ECU assembly) connectors.
    2. Disconnect the 2N and 2O driver side junction block assembly connectors.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F113-9 (ACCD) -2N-23 Always Below 1 Ω
      F114-3 (IG1D) -2N-22 Always Below 1 Ω
      2O-1 - Body ground Always Below 1 Ω
      F113-9 (ACCD) or 2N-23 - Body ground Always 10 kΩ or higher
      F114-3 (IG1D) or 2N-22 - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  9

  9. CHECK DRIVER SIDE JUNCTION BLOCK ASSEMBLY (IG NO. 1, IG NO. 3, IG NO. 4, IG NO. 5, ACC RELAY) 
    1. Remove the driver side junction block assembly.

      Refer to REMOVAL [08/2019 - ]

    2. Measure the resistance according to the value(s) in the table below.
      GTY872089Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component without harness connected
      (Driver Side Junction Block Assembly)      		 - -

      Standard Resistance

      Tester Connection Condition Specified Condition
      2N-22 - 2O-1 20°C (68°F) 87.32 to 127.14 Ω
      2N-23 - 2O-1 20°C (68°F) 130.92 to 190.74 Ω
      2K-1 - 2Q-36 Battery voltage applied to terminals 2N-22 and 2O-1 Below 1 Ω
      Battery voltage not applied to terminals 2N-22 and 2O-1 10 kΩ or higher
      2K-1 - 2N-42 Battery voltage applied to terminals 2N-22 and 2O-1 Below 1 Ω
      Battery voltage not applied to terminals 2N-22 and 2O-1 10 kΩ or higher
      2K-1 - 2O-22 Battery voltage applied to terminals 2N-22 and 2O-1 Below 1 Ω
      Battery voltage not applied to terminals 2N-22 and 2O-1 10 kΩ or higher
      2K-1 - 2N-2 Battery voltage applied to terminals 2N-22 and 2O-1 Below 1 Ω
      Battery voltage not applied to terminals 2N-22 and 2O-1 10 kΩ or higher
      2K-1 - 2N-50 Battery voltage applied to terminals 2N-23 and 2O-1 Below 1 Ω
      Battery voltage not applied to terminals 2N-23 and 2O-1 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE DRIVER SIDE JUNCTION BLOCK ASSEMBLY. Refer to  REMOVAL [08/2019 - ] 

    Result: 

    OK 

    See step  10

  10. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 
    1. Measure the voltage while confirming the power source mode on the Data List.
      GTY882077Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Certification ECU (Smart Key ECU Assembly))      		 - -
      BODY ELECTRICAL > POWER SOURCE CONTROL > DATA LIST

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Power Supply Condition Power supply state All OFF, ACC ON, IG ON or ST ON All OFF: Engine switch off (ACC and IG)
      ACC ON: Engine switch on (ACC)
      IG ON: Engine switch on (IG)
      ST ON: Sending engine start request signal      		 -

      Standard Voltage

      Tester Connection Condition Specified Condition
      F114-3 (IG1D) - Body ground Engine switch off 1 V or less
      Engine switch on (ACC) 1 V or less
      Engine switch on (IG) 9 V or higher
      F113-9 (ACCD) - Body ground Engine switch off 1 V or less
      Engine switch on (ACC) 8.5 V or higher
      Engine switch on (IG) 8.5 V or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2019 - ] 

    Result: 

    NG 

    See step  11

  11. READ VALUE USING TECHSTREAM (START SWITCH1, START SWITCH2) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Power Source Control / Data List.
    5. Read the Data List according to the display on the Techstream.
      BODY ELECTRICAL > POWER SOURCE CONTROL > DATA LIST

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Start Switch1 Engine switch 1 status OFF or ON OFF: Engine switch not pressed
      ON: Engine switch pressed
      • If the engine switch is pressed for a short time, the display may not change.
      • Use this item to determine whether the engine switch input signal is malfunctioning.
      Start Switch2 Engine switch 2 status OFF or ON OFF: Engine switch not pressed
      ON: Engine switch pressed
      • Backup for engine switch 1. However, when the engine switch is pressed and held, the control functions only when both engine switch 1 and 2 are normal.
      • Behaves the same way as engine switch 1.

      OK

      The Techstream display changes correctly in response to the engine switch operation.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [08/2019 - ] 

    Result: 

    NG 

    See step  13

  12. INSPECT TRANSMITTER BATTERY 
    1. Inspect the transmitter battery.

      Refer to INSPECTION [08/2019 - ]

      NOTE:

      Do not wrap the lead wire around a terminal, wedge it between terminals, or solder it. The terminal may be deformed or damaged, and the transmitter battery will not be able to be installed correctly.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE ELECTRICAL KEY TRANSMITTER SUB-ASSEMBLY. Refer to  REMOVAL [08/2019 - ] 

    Result: 

    NG 

    REPLACE TRANSMITTER BATTERY. Refer to  REPLACEMENT [08/2019 - ] 

  13. INSPECT ENGINE SWITCH 
    1. Remove the engine switch.

      Refer to REMOVAL [08/2015 - ]

    2. Inspect the engine switch.

      Refer to INSPECTION [08/2019 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE ENGINE SWITCH. Refer to  REMOVAL [08/2015 - ] 

    Result: 

    OK 

    See step  14

  14. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ENGINE SWITCH) 
    1. Disconnect the F113 certification ECU (smart key ECU assembly) connector.
    2. Disconnect the F106 engine switch connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F113-16 (SSW1) - F106-5 (SS1) Always Below 1 Ω
      F113-18 (SSW2) - F106-1 (SS2) Always Below 1 Ω
      F113-12 (AGND) - F106-6 (AGND) Always Below 1 Ω
      F113-16 (SSW1) or F106-5 (SS1) - Body ground Always 10 kΩ or higher
      F113-18 (SSW2) or F106-1 (SS2) - Body ground Always 10 kΩ or higher
      F113-12 (AGND) or F106-6 (AGND) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [08/2019 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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