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Home >> Lexus >> 2015 >> GS 450h Base >> Repair and Diagnosis >> Electrical >> Starter >> Smart Access System With Push-Button Start (For Start Function) (Diagnostic Codes & Symptom Tests) >> SMART ACCESS SYSTEM WITH PUSH-BUTTON START (for Start Function) >> Symptom Tests >> Power Source Mode does not Change to ON (IG and ACC) [10/2015 - ] >> Procedure
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Power Source Mode does not Change to ON (IG and ACC) [10/2015 - ]: 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 FLOWCHART (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 [09/2014 - ] )

    Result:  OK

    OK 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (POWER SOURCE) 

    Refer to DTC B2271: Ignition Hold Monitor Malfunction [10/2015 - ] 

    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 PUSH-BUTTON START FUNCTION 
    1. Remove the battery from the electrical key transmitter sub-assembly (Refer to REPLACEMENT [09/2014 - ] ).
    2. With the brake pedal depressed, hold the electrical key transmitter near the power switch and check if the power source mode changes.
      GTY537386Courtesy 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

    Result:  B

    B 

    See step  8

    Result:  A

    A 

    See step  5

  5. READ VALUE USING TECHSTREAM (STOP LIGHT SWITCH 1) 
    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 hybrid control system cannot be started when this item is OFF.
      • When this item is malfunctioning, the hybrid control system can be started by pressing and holding the power switch for a certain period of time.

      OK

      ON (brake pedal is depressed) and OFF (brake pedal is released) appear on the screen.

    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: Power switch off
      ACC ON: Power switch on (ACC) (ACC relay on)
      IG1 ON: Power switch on (IG) (IG1 relay on)
      IG2 ON: Power switch on (IG) (IG2 relay on)
      ST ON: Sending hybrid control system 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 power switch off and brake pedal depressed, hold the electrical key transmitter sub-assembly near the power switch for 2 seconds or more and read the Data List.

      OK

      IG2 ON is displayed in the Data List.

      HINT: 

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

    Result:  NG

    NG 

    See step  13

    Result:  OK

    OK 

    See step  7

  7. CHECK POWER MANAGEMENT CONTROL ECU 
    1. Read the Data List according to the display on the Techstream.
    2. Measure the voltage according to the value(s) in the table below.
      GTY534395Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Power Management Control ECU)
    3. 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: Power switch off (ACC and IG)
      ACC ON: Power switch on (ACC) (ACC relay on)
      IG1 ON: Power switch on (IG) (IG1 relay on)
      IG2 ON: Power switch on (IG) (IG2 relay on)
      ST ON: Sending hybrid control system 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 Techstream.

      Standard Voltage

      Tester Connection Condition Specified Condition
      N92-2 (IG1D) - Body ground Power switch off 1 V or less
      Power switch on (ACC)
      Power switch on (IG) 9 V or higher
      A36-2 (IG2D) - Body ground Power switch off 1 V or less
      Power switch on (ACC)
      Power switch on (IG) 9 V or higher
      N92-1 (ACCD) - Body ground Power switch off 1 V or less
      Power switch on (IG) 8.5 V or higher
      Power switch on (ACC)

    Result:  OK

    OK 

    CHECK RELAY CONTACT SIDE CIRCUIT 

    Result:  NG

    NG 

    REPLACE POWER MANAGEMENT CONTROL ECU 

    (Refer to REMOVAL [09/2014 - ] )

  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 Power switch 1 status/ON or OFF ON: Power switch pressed
      OFF: Power switch not pressed
      • If the power switch is pressed for a short time, the display may not change.
      • Use this item to determine whether the power switch input signal is malfunctioning.
      Start Switch2 Power switch 2 status/ON or OFF ON: Power switch pressed
      OFF: Power switch not pressed
      • Backup for power switch 1. However, when the power switch is pressed and held, the control functions only when both power switch 1 and 2 are normal.
      • Behaves the same way as power switch 1.

      OK

      ON (Power switch is pressed) and OFF (Power switch is not pressed) appear on the screen.

      Result

      Result Proceed to
      NG A
      OK B

    Result:  B

    B 

    GO TO OTHER FLOWCHART (Room Oscillator does not Recognize Key) 

    (Refer to Room Oscillator does not Recognize Key [09/2014 - ] )

    Result:  A

    A 

    See step  9

  9. INSPECT POWER SWITCH 
    1. Inspect the power switch (Refer to INSPECTION [09/2014 - ] ).

    Result:  NG

    NG 

    REPLACE POWER SWITCH 

    (Refer to REMOVAL [09/2014 - ] )

    Result:  OK

    OK 

    See step  10

  10. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - POWER SWITCH) 
    1. Disconnect the N91 and N92 connectors from the power management control ECU.
    2. Disconnect the N43 connector from the power switch.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      N91-7 (SSW1) - N43-5 (SS1) Always Below 1 Ω
      N91-17 (SSW2) - N43-1 (SS2)
      N91-7 (SSW1) or N43-5 (SS1) - Body ground 10 kΩ or higher
      N92-17 (SSW2) or N43-1 (SS2) - Body ground

    Result:  OK

    OK 

    REPLACE POWER MANAGEMENT CONTROL ECU 

    (Refer to REMOVAL [09/2014 - ] )

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  11. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - STOP LIGHT SWITCH ASSEMBLY) 

    See step  4

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  12

  12. INSPECT STOP LIGHT SWITCH ASSEMBLY 

    See step  14

    Result:  OK

    OK 

    REPLACE POWER MANAGEMENT CONTROL ECU 

    (Refer to REMOVAL [09/2014 - ] )

    Result:  NG

    NG 

    REPLACE STOP LIGHT SWITCH ASSEMBLY 

    (Refer to REMOVAL [09/2014 - ] )

  13. CHECK FOR DTC 
    1. Enter the following menus: Body Electrical / Smart Access / Trouble Codes.
    2. Check for DTCs.

      Result

      Result Proceed to
      The following DTCs are not output:
      • B2785
      • B2287
      • B2784
      • B278A
      		 A
      DTC B2785 is not output but DTC B2287 is output. B
      DTCs other than B2287 are output. C

    Result:  A

    A 

    REPLACE ELECTRICAL KEY TRANSMITTER SUB-ASSEMBLY 

    (Refer to REMOVAL [09/2014 - ] )

    Result:  B

    B 

    GO TO OTHER FLOWCHART (DTC B2287) 

    (Refer to DTC B2287: LIN Communication Master Malfunction [09/2014 - ] )

    Result:  C

    C 

    GO TO OTHER FLOWCHART 

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