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Power Source Mode does not Change to ON (IG and ACC) [08/2015 - 08/2019]: Procedure

  1. CHECK HARNESS AND CONNECTOR (BATTERY - POWER MANAGEMENT CONTROL ECU) 

    See step  1

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - BODY GROUND) 

    See step  2

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  3

  3. READ VALUE USING TECHSTREAM (KEY CERTIFI WAIT T-OUT) 
    1. Connect the Techstream to the DLC3.
    2. Turn the Techstream on.

      HINT: 

      When using the Techstream with the engine switch off, turn any of the door courtesy light switches on and off repeatedly at intervals of 1.5 seconds or less until communication between the tester and vehicle starts.

    3. Enter the following menus: Body Electrical / Power Source Control / Data List.
    4. Read the Data List and check that "No" is displayed 1 second after turning the engine switch from off to on (IG).
      POWER SOURCE CONTROL

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Key Certifi Wait T-Out Key certification waiting timed out / Yes or No Yes: Key certification waiting timed out
      No: Key certification completed within specified time      		 -

      OK

      "No" is displayed 1 second after turning the engine switch from off to on (IG).

    Result: 

    NG 

    See step  9

    Result: 

    OK 

    See step  4

  4. READ VALUE USING TECHSTREAM (START SWITCH 1, 2) 
    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. According to the display on the Techstream, read the Data List.
      POWER SOURCE CONTROL

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Start Switch1 Start Switch 1 / ON or OFF ON: Engine switch pushed
      OFF: Engine switch not pushed      		 -
      Start Switch2 Start Switch 2 / ON or OFF ON: Engine switch pushed
      OFF: Engine switch not pushed      		 -

      OK

      The display changes in response to the operation of the engine switch.

    Result: 

    NG 

    See step  7

    Result: 

    OK 

    See step  5

  5. CHECK POWER MANAGEMENT CONTROL ECU 
    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 and check that the display changes according to the changes in the power source mode when the engine switch is pushed.
      POWER SOURCE CONTROL

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Power Supply Condition Power Supply Condition / IG2 ON, ST ON, All OFF, IG1 ON or ACC ON IG2 ON: IG2 relay on
      ST ON: ST request signal on
      All OFF: All relays off
      IG1 ON: IG1 relay on
      ACC ON: ACC relay on      		 -

      OK

      Display changes according to the changes in the power source mode when the engine switch is pushed.

    6. Measure the voltage according to the value(s) in the table below.
      GTY694322Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Power Management Control ECU)      		 - -

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      F80-20 (IG1D) - Body ground Engine switch off Below 1 V
      Engine switch on (ACC)
      Engine switch on (IG) ((Voltage at terminal AM21 or AM22) minus 2.0 V) or higher
      F81-8 (IG2D) - Body ground Engine switch off Below 1 V
      Engine switch on (ACC)
      Engine switch on (IG) ((Voltage at terminal AM21 or AM22) minus 2.0 V) or higher
      F80-19 (ACCD) - Body ground Engine switch off Below 1 V
      Engine switch on (ACC) ((Voltage at terminal AM21 or AM22) minus 2.0 V) or higher
      Engine switch on (IG) ((Voltage at terminal AM21 or AM22) minus 2.0 V) or higher

    Result: 

    NG 

    REPLACE POWER MANAGEMENT CONTROL ECU 

    (Refer to REMOVAL [08/2015 - 08/2019] )

    Result: 

    OK 

    See step  6

  6. CONFIRMATION TEST 
    1. Check that the power source mode changes to on (ACC) and on (IG) when operating the engine switch.

      OK

      The power source mode changes to on (ACC) and on (IG) in response to the operation of the engine switch.

    Result: 

    OK 

    USE SIMULATION METHOD TO CHECK 

    (Refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2015 - 08/2019] )

    Result: 

    NG 

    CHECK RELAY CONTACT SIDE CIRCUIT 

  7. INSPECT ENGINE SWITCH 
    1. Remove the engine switch.
      GTY732869Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      7 (SS1) - 5 (GND) Engine switch not pushed 10 kΩ or higher
      Engine switch pushed Below 1 Ω
      2 (SS2) - 5 (GND) Engine switch not pushed 10 kΩ or higher
      Engine switch pushed Below 1 Ω
      TEXT IN ILLUSTRATION

      *a Component without harness connected
      (Engine Switch)

    Result: 

    NG 

    REPLACE ENGINE SWITCH 

    (Refer to REMOVAL [08/2015 - ] )

    Result: 

    OK 

    See step  8

  8. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - ENGINE SWITCH) 
    1. Disconnect the F80 power management control ECU connector.
    2. Disconnect the F71 engine switch connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F80-17 (SSW2) - F71-2 (SS2) Always Below 1 Ω
      F80-18 (SSW1) - F71-7 (SS1)
      F80-17 (SSW2) - Body ground Always 10 kΩ or higher
      F80-18 (SSW1) - Body ground
      F71-5 (GND) - Body ground Always Below 1 Ω

    Result: 

    OK 

    REPLACE POWER MANAGEMENT CONTROL ECU 

    (Refer to REMOVAL [08/2015 - 08/2019] )

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  9. CHECK FOR DTC 
    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 / Trouble Codes.
    5. Read the DTCs.
    6. Enter the following menus: Body Electrical / Smart Key / Trouble Codes.
    7. Read the DTCs.
      RESULT

      Result Proceed to
      None of the following DTCs are output:
      B2785 Communication Malfunction between ECUs Connected by LIN
      B2287 LIN Communication Master Malfunction
      B2784 Antenna Coil Open/Short      		 A
      DTC B2287 is output but B2785 is not output. B
      A DTC other than B2287 is output. C

    Result: 

    A 

    GO TO SMART KEY SYSTEM (FOR ENTRY FUNCTION) (Room Oscillator does not Recognize Key) 

    (Refer to Room Oscillator does not Recognize Key [08/2015 - 08/2019] )

    Result: 

    B 

    GO TO DTC (B2287) 

    (Refer to DTC B2287: LIN Communication Master Malfunction; DTC B278C: Lost Communication with Power Source Control [08/2015 - 08/2019] )

    Result: 

    C 

    GO TO DTC CHART 

    (Refer to DIAGNOSTIC TROUBLE CODE CHART [08/2015 - 08/2019] )

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