SMART ENTRY AND START SYSTEM (for Start Function) Power Source Mode does not Change to ON (IG and ACC)

DESCRIPTION

If any of the following operations are performed, the certification ECU (smart key ECU assembly) receives a signal, and changes the power source mode.


WIRING DIAGRAM

A01G5NSE02
A01G6L8E08

INSPECTION PROCEDURE

Note


  • When using the GTS with the vehicle engine switch off, connect the GTS to the vehicle and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the GTS and the vehicle begins. Then select the Model Code "KEY REGIST" under manual mode and enter the following menus: Body Electrical / Entry&Start(CAN). While using the GTS, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the GTS and the vehicle.

  • The smart entry and start system (for Start Function) uses a multiplex communication system (LIN communication system) and the CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting Click here. Troubleshoot the smart entry and start system (for Start Function) after confirming that the communication systems are functioning properly.

  • Make sure that no DTCs are output. If any DTCs are output, proceed to the Diagnostic Trouble Code Chart Click here.

  • If the smart entry and start system is disabled through the customize function, enable the system before performing troubleshooting Click here.

  • Before replacing the certification ECU (smart key ECU assembly) or electrical key transmitter sub-assembly, refer to the smart entry and start system (for Start Function) precaution Click here.

  • Inspect the fuses of circuits related to this system before performing the following inspection procedure.

  • After completing repairs, confirm that the problem does not occur.

Tech Tips

Related Data List and Active Test Items
Problem Symptom Data List Item Active Test Item
Power source mode does not change to on (IG) or on (ACC)

    Power Source Control

  • Start Switch1

  • Start Switch2

  • Power Supply Condition

  • IG1 Relay Monitor(Inside)

  • IG2 Relay Monitor(Inside)

  • IG1 Relay Monitor(Outside)

  • IG2 Relay Monitor(Outside)

  • Latch Circuit

  • ACC Relay Monitor

 -

PROCEDURE


  1. CHECK WIRELESS DOOR LOCK CONTROL SYSTEM


    1. Check the wireless door lock function by operating the electrical key transmitter sub-assembly Click here.

      OK
      Wireless door lock function operates.

    NG

    GO TO OTHER FLOW CHART (All Door Entry Lock/Unlock Functions and Wireless Functions do not Operate) Click here

    OK

  2. CHECK HARNESS AND CONNECTOR (POWER SOURCE)

    A01G791E26
    Text in Illustration
    *a

    Rear view of wire harness connector

    (to Certification ECU (smart key ECU assembly))

    1. Disconnect the A36 certification ECU (smart key ECU assembly) connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A36-2 (+B) - Body ground Always 11 to 14 V

    NG

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

    OK

  3. CHECK HARNESS AND CONNECTOR (GROUND)

    A01G791E27
    Text in Illustration
    *a

    Rear view of wire harness connector

    (to Certification ECU (smart key ECU assembly))

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A36-11 (E) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK SMART ENTRY AND START SYSTEM


    1. Remove the battery from the electrical key transmitter sub-assembly Click here.

    2. A01G5R1E01
      Text in Illustration
      *1 Engine Switch
      *2 Electrical Key Transmitter Sub-assembly

      With the brake pedal depressed, hold the electrical key transmitter near the engine switch and check if the power source mode changes.

      OK
      The power source mode changes.

      Tech Tips

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

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

    B

    READ VALUE USING GTS Click here

    A

  5. READ VALUE USING GTS


    1. Connect the GTS to the DLC3.

    2. Turn the GTS on.

    3. Enter the following menus: Body Electrical / Power Source Control / Data List.

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

      Power Source Control
      Tester Display Measurement Item/Range Normal Condition Specified Condition
      Stop Light Switch1 State of brake pedal/ON or OFF

      ON: Brake pedal depressed

      OFF: Brake pedal released

      • Use this item to determine whether the stop light switch is malfunctioning.

      • The engine cannot be started when this item is OFF.

      • When this item is malfunctioning, the engine can be started by pressing and holding the engine switch for a certain period of time.
      OK
      ON (brake pedal is depressed) and OFF (brake pedal is released) appear on the screen.

    NG

    Click here

    OK

  6. READ VALUE USING GTS


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

      Power Source Control
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Power Supply Condition Power supply state/IG2 ON, ST ON, All OFF, IG1 ON or ACC ON

      ALL OFF: Engine switch off

      ACC ON: Engine switch on (ACC) (ACC relay on)

      IG1 ON: Engine switch on (IG) (IG1 relay on)

      IG2 ON: Engine switch on (IG) (IG2 relay on)

      ST ON: Sending engine start request signal

      		 Since the IG1 and IG2 relays turn on at approximately the same time, IG1 ON may not be displayed (the IG1 relay turns on for a very short time).

    2. With the engine switch off and brake pedal depressed, hold the electrical key transmitter sub-assembly near the engine switch for 2 seconds or more and read the Data List.

      OK
      IG2 ON is displayed in the Data List.

      Tech Tips

      If the smart key function has been canceled on the customization menu, ACC ON is displayed in the Data List.


    NG

    CHECK FOR DTC Click here

    OK

  7. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)


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

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

      A01G7SQE26
      Text in Illustration
      *a

      Component with harness connected

      (Certification ECU (Smart Key ECU Assembly))

      		 - -

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

      Power Source Control
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Power Supply Condition Power supply state/IG2 ON, ST ON, All OFF, IG1 ON or ACC ON

      All OFF: Engine switch off (ACC and IG)

      ACC ON: Engine switch on (ACC)

      IG1 ON: Engine switch on (IG) (IG1 relay on)

      IG2 ON: Engine switch on (IG) (IG2 relay on)

      ST ON: Sending engine start request signal

      		 Since the IG1 and IG2 relays turn on at approximately the same time, IG1 ON may not be displayed (the IG1 relay turns on for a very short time).

    4. Measure the voltage while checking the Data List on the GTS.

      Standard Voltage
      Tester Connection Condition Specified Condition
      H56-6 (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
      A36-9 (IG2D) - 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
      H56-4 (ACCD) - Body ground Engine switch off 1 V or less
      Engine switch on (IG) 8.5 V or higher
      Engine switch on (ACC) 8.5 V or higher

    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

    OK

    CHECK RELAY CONTACT SIDE CIRCUIT

  8. READ VALUE USING GTS


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

      Power Source Control
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Start Switch1 Engine switch 1 status/ON or OFF

      ON: Engine switch pressed

      OFF: Engine switch not 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/ON or OFF

      ON: Engine switch pressed

      OFF: Engine switch not 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
      ON (Engine switch is pressed) and OFF (Engine switch is not pressed) appear on the screen.
      Result
      Result Proceed to
      NG A
      OK B

    B

    GO TO OTHER FLOW CHART (Room Oscillator does not Recognize Key) Click here

    A

  9. INSPECT ENGINE SWITCH


    1. Inspect the engine switch Click here for 2GR-FE, Click here for 2AR-FE).

      Result
      Result Proceed to
      OK A
      NG (for 2GR-FE) B
      NG (for 2AR-FE) C

    B

    REPLACE ENGINE SWITCH Click here

    C

    REPLACE ENGINE SWITCH Click here

    A

  10. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ENGINE SWITCH)


    1. Disconnect the H56 certification ECU (smart key ECU assembly) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H56-28 (SSW1) - H44-5 (SS1) Always Below 1 Ω
      H56-30 (SSW2) - H44-1 (SS2) Always Below 1 Ω
      H56-28 (SSW1) or H44-5 (SS1) - Body ground Always 10 kΩ or higher
      H56-30 (SSW2) or H44-1 (SS2) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

  11. CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH ASSEMBLY - POWER SOURCE AND BODY GROUND)


    1. A01G768E66
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Stop Light Switch Assembly)

      Disconnect the A28 stop light switch assembly connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A28-1 (B) - A28-3 (GND) Engine switch off 11 to 14 V
      Standard Resistance
      Tester Connection Condition Specified Condition
      A28-3 (GND) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  12. CHECK STOP LIGHT SWITCH ASSEMBLY


    1. A01G91LE67
      Text in Illustration
      *a

      Component with harness connected

      (Stop Light Switch Assembly)

      Reconnect the A28 stop light switch assembly connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A28-2 (L) - A28-3 (GND) Engine switch off, brake pedal not depressed Below 1 V
      A28-2 (L) - A28-3 (GND) Engine switch off, brake pedal depressed 11 to 14 V

    NG

    REPLACE STOP LIGHT SWITCH ASSEMBLY Click here

    OK

  13. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - STOP LIGHT SWITCH ASSEMBLY)


    1. Disconnect the A28 stop light switch assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A36-18 (STP1) - A28-2 (L) Always Below 1 Ω
      A36-18 (STP1) or A28-2 (L) - Body ground Always 10 kΩ or higher
    3. A01G4DDE07
      Text in Illustration
      *a

      Rear view of wire harness connector

      (Certification ECU (Smart Key ECU Assembly))

      Reconnect the A28 stop light switch assembly connector.

    4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A36-18 (STP1) - Body ground Brake pedal released 1 V or less
      Brake pedal depressed 9 V or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

  14. CHECK FOR DTC


    1. Enter the following menus:

      for Entry&Start: Body Electrical / Entry&Start / Trouble Codes.

    2. Check for DTCs.

      Result
      Result Proceed to

      The following DTCs are not output:


      • B2784

      • B287A

      		 A
      DTC B2784 is output. B
      DTC B278A is output. C

    B

    GO TO OTHER FLOW CHART (DTC B2784) Click here

    C

    GO TO OTHER FLOW CHART (DTC B278A) Click here

    A

    REPLACE ELECTRICAL KEY TRANSMITTER SUB-ASSEMBLY