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

  1. CHECK DTC (ALL) 
    1. Using the Techstream, confirm the output of DTCs for all systems.

      OK

      No DTCs are output.

      NOTE:
      • When using the Techstream with the engine switch off, perform either of the following: 1) Turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the Techstream and vehicle begins, or 2) connect the Techstream to the vehicle, select the vehicle type under manual mode, and then enter the following menus: Body Electrical / Smart Access / Trouble Codes.
      • Make sure that no DTCs are output. If any DTCs are output, proceed to the Diagnostic Trouble Code Chart.

    Result: 

    NG 

    GO TO DTC CHART. Refer to the appropriate service information 

    Result: 

    OK 

    See step  2

  2. CHECK WIRELESS DOOR LOCK CONTROL SYSTEM 
    1. Check that the wireless lock and unlock functions operate normally.

      OK

      Wireless lock and unlock functions operate normally.

      HINT: 

      If the wireless lock and unlock functions operate normally, it can be determined that some functions of the key and certification ECU operate normally.

    Result: 

    NG 

    GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START (for Entry Function) (PROBLEM SYMPTOMS TABLE) 

    (Refer to PROBLEM SYMPTOMS TABLE [08/2015 - 08/2019] )

    Result: 

    OK 

    See step  3

  3. INSPECT SMART ACCESS SYSTEM WITH PUSH-BUTTON START 
    1. Remove the battery of the electrical key transmitter.
      GTY280514Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. With the brake pedal depressed, touch the key to the engine switch.
    3. Press and hold the engine switch for a maximum of 15 seconds and check if the engine can be started.

      OK

      The engine can be started.

      HINT: 

      • If the engine can be started, it is clear that the key is not being detected properly inside the vehicle. There may be a problem with the formation of the interior detection area, a problem with the indoor electrical key antenna (reception problem), or wave interference.
      • If the engine cannot be started, there is a problem with the engine switch, power management control ECU or a related wire harness.

    Result: 

    OK 

    GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START (for Entry Function) (ROOM OSCILLATOR DOES NOT RECOGNIZE KEY) 

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

    Result: 

    NG 

    See step  4

  4. READ VALUE USING TECHSTREAM (START SWITCH 1, 2) 
    1. Connect the Techstream to the DLC3.
    2. Turn the Techstream on.
      NOTE:

      When using the Techstream with the engine switch off, perform the following: Turn a courtesy light switch on and off as intervals of 1.5 seconds or less until communication between the Techstream and vehicle begins.

    3. Enter the following menus: Body Electrical / Power Source Control / Data List.
    4. 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 Condition of engine switch contact 1/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 Condition of engine switch contact 2/ON or OFF ON: Engine switch pressed
      OFF: Engine switch not pressed
      • This is the backup for engine switch 1.
      • Behaves the same way as engine switch 1.

      OK

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

    Result: 

    NG 

    See step  8

    Result: 

    OK 

    See step  5

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

    See step  1

    Result: 

    NG 

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

    Result: 

    OK 

    See step  6

  6. 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  7

  7. CHECK POWER MANAGEMENT CONTROL ECU 
    1. Connect the power management control ECU connectors.
    2. Connect the Techstream to the DLC3.
    3. Turn the Techstream on.
      NOTE:

      When using the Techstream with the engine switch off, perform the following: Turn a courtesy light switch on and off as intervals of 1.5 seconds or less until communication between the Techstream and vehicle begins.

    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 State of power supply/IG2 ON, ST ON, All OFF, IG1 ON or ACC ON All OFF: Engine switch off (power supply 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: Cranking engine (ST request signal on)      		 Since IG1 ON and IG2 ON turn "on" at approximately the same time, IG1 ON may not be displayed (IG1 ON turns on for a very short time).

      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.
      GTY652657Courtesy 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
      G39-20 (IG1D) - Body ground Engine switch off 1 V or less
      Engine switch on (ACC)*1
      Engine switch on (IG)*2 9 V or higher
      G38-8 (IG2D) - Body ground Engine switch off 1 V or less
      Engine switch on (ACC)*1
      Engine switch on (IG)*2 9 V or higher
      G39-19 (ACCD) - Body ground Engine switch off 1 V or less
      Engine switch on (ACC)*1 8.5 V or higher
      Engine switch on (IG)*2 8.5 V or higher

      HINT: 

      1. *1: To turn the engine switch on (ACC), carry the key and press the engine switch with the shift lever in P and the brake pedal released.
      2. *2: To turn the engine switch on (IG), carry the key and press the engine switch twice with the shift lever in P and the brake pedal released.

    Result: 

    OK 

    USE SIMULATION METHOD TO CHECK 

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

    Result: 

    NG 

    REPLACE POWER MANAGEMENT CONTROL ECU 

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

  8. INSPECT ENGINE SWITCH 
    1. Remove the engine switch.
      GTY215087Courtesy 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 - 08/2019] )

    Result: 

    OK 

    See step  9

  9. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - ENGINE SWITCH) 
    1. Disconnect the G39 power management control ECU connector.
    2. Disconnect the G24 engine switch connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      G39-17 (SSW2) - G24-2 (SS2) Always Below 1 Ω
      G39-18 (SSW1) - G24-7 (SS1)
      G39-17 (SSW2) - Body ground Always 10 kΩ or higher
      G39-18 (SSW1) - Body ground
      G24-5 (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 

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