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Power Source Mode does not Change to ON (IG and ACC) (07/2015 -): Procedure

  1. CHECK WIRELESS DOOR LOCK CONTROL SYSTEM 
    1. Check the wireless door lock function by operating the electrical key transmitter sub-assembly.

      OK

      Wireless door lock function operates.

    Result:  NG

    NG 

    GO TO OTHER DIAGNOSTIC PROCEDURE (All Door Entry Lock/Unlock Functions and Wireless Functions do not Operate) 

    (Refer to All Door Entry Lock/Unlock Functions and Wireless Functions do not Operate (07/2015 -) )

    Result:  OK

    OK 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (POWER SOURCE) 

    See step  1

    Result:  NG

    NG 

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

    Result:  OK

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (GROUND) 

    See step  2

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  4

  4. CHECK SMART ACCESS SYSTEM WITH PUSH-BUTTON START 
    1. Remove the battery from the electrical key transmitter sub-assembly (Refer to REPLACEMENT (07/2015 -) ).
    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.
      GTY634863Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK

      The power source mode changes.

      HINT: 

      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
      TEXT IN ILLUSTRATION

      *1 Engine Switch
      *2 Electrical Key Transmitter Sub-assembly

    Result:  B

    B 

    See step  8

    Result:  A

    A 

    See step  5

  5. READ VALUE USING TECHSTREAM 
    1. Connect the Techstream to the DLC3.
    2. Turn the Techstream on.
    3. Enter the following menus: Body Electrical / Power Source Control / Data List.
    4. Read the Data List according to the display on the Techstream.
      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

      The Techstream display changes correctly in response to the brake pedal operation.

    Result:  NG

    NG 

    See step  11

    Result:  OK

    OK 

    See step  6

  6. READ VALUE USING TECHSTREAM 
    1. Read the Data List according to the display on the Techstream.
      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 on the Techstream screen.

      HINT: 

      If the smart access system with push-button start (for Start Function) function has been canceled on the customization menu, ACC ON is displayed on the Techstream screen.

    Result:  NG

    NG 

    See step  14

    Result:  OK

    OK 

    See step  7

  7. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 
    1. Measure the voltage according to the value(s) in the table below.
      GTY673045Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Certification ECU (Smart Key ECU Assembly)      		 - -
    2. Read the Data List according to the display on the Techstream.
      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).
    3. Measure the voltage while reading the Data List on the Techstream.

      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

    Result:  OK

    OK 

    CHECK RELAY CONTACT SIDE CIRCUIT 

    Result:  NG

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 

    (Refer to REMOVAL (07/2015 -) )

  8. READ VALUE USING TECHSTREAM 
    1. Read the Data List according to the display on the Techstream.
      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 Switch 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

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

      Result

      Result Proceed to
      NG A
      OK B

    Result:  B

    B 

    GO TO DIAGNOSTIC PROCEDURE (Room Oscillator does not Recognize Key) 

    (Refer to Room Oscillator does not Recognize Key (07/2015 -) )

    Result:  A

    A 

    See step  9

  9. INSPECT ENGINE SWITCH 
    1. Inspect the engine switch (Refer to INSPECTION (07/2015 -) ).

    Result:  NG

    NG 

    REPLACE ENGINE SWITCH 

    (Refer to REMOVAL (07/2015 -) )

    Result:  OK

    OK 

    See step  10

  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

    Result:  OK

    OK 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 

    (Refer to REMOVAL (07/2015 -) )

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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

    See step  21

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  12

  12. CHECK STOP LIGHT SWITCH ASSEMBLY 

    See step  22

    Result:  NG

    NG 

    REPLACE STOP LIGHT SWITCH ASSEMBLY 

    (Refer to REMOVAL (07/2015 -) )

    Result:  OK

    OK 

    See step  13

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

    See step  4

    Result:  OK

    OK 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 

    (Refer to REMOVAL (07/2015 -) )

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  14. CHECK FOR DTC 
    1. Check for DTCs (Refer to DTC CHECK / CLEAR (07/2015 -) ).

      Result

      Result Proceed to
      The following DTCs are not output:
      • B2784
      • B287A
      		 A
      DTC B2784 is output. B
      DTC B278A is output. C

    Result:  A

    A 

    REPLACE ELECTRICAL KEY TRANSMITTER SUB-ASSEMBLY 

    Result:  B

    B 

    GO TO DIAGNOSTIC TROUBLE CODE CHART (DTC B2784) 

    (Refer to DTC B2784: Antenna Coil Open / Short (07/2015 -) )

    Result:  C

    C 

    GO TO DIAGNOSTIC TROUBLE CODE CHART (DTC B278A) 

    (Refer to DTC B278A: Short to GND in Immobilizer System Power Source Circuit (07/2015 -) )

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