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Power Source Mode does not Change to ON (IG and ACC): Procedure

WARNING: This page is about a different car, the 2011 Lexus RX 350. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK DTC 
    1. Connect the Techstream to the DLC3.
    2. Turn the Techstream on.
    3. Turn on and off any of the door courtesy light switches repeatedly at 1.5-second intervals or less until communication between the Techstream and vehicle starts.
    4. Enter the following menus: Body Electrical / All ECUs / Health Check.
    5. Clear the DTC.
    6. Check for DTCs again.

      OK

      DTCs are not output.

    NG → GO TO  DIAGNOSTIC TROUBLE CODE CHART 

    OK: Go to next step 

  2. CHECK SMART ACCESS SYSTEM WITH PUSH-BUTTON START 
    1. Remove the battery of the electrical key transmitter. Refer to REMOVAL .
      Fig 1: Touching Logo Side Mark Of Key Or Card Key To Engine Switch
      GTY275296Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Touch the logo side mark of the key or card key to the engine switch.
    3. Check that the engine switch can be turned on (IG).

      OK

      Power source mode can be changed.

    NG → See step   8 

    OK: Go to next step 

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

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - POWER MANAGEMENT CONTROL ECU) 

    OK: Go to next step 

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

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER MANAGEMENT CONTROL ECU - BODY GROUND) 

    OK: Go to next step 

  5. READ VALUE USING TECHSTREAM 
    1. Reconnect the F8 connector to the power management control ECU.
    2. Enter the following menus: Body Electrical / Power Source Control / Data List.
    3. 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 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

      ON (engine switch is pushed) and OFF (engine switch is not pushed) appear on the screen.

    NG → See step   6 

    OK → See step   9 

  6. INSPECT ENGINE SWITCH 
    1. Remove the engine switch. Refer to REMOVAL .
      Fig 2: Identifying Engine Switch Connector Terminals
      GTY252514Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

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

      *1 Component without harness connected
      (Engine Switch)

    NG → See step   10 

    OK: Go to next step 

  7. CHECK HARNESS AND CONNECTOR (ENGINE SWITCH - POWER MANAGEMENT CONTROL ECU AND BODY GROUND) 
    1. Disconnect the F8 connector from the power management control ECU.
      Fig 3: F22 & F8 Connector
      GTY348525Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F22-7 (SS1) - F8-18 (SSW1) Always Below 1 Ω
      F22-7 (SS1) - Body ground Always 10 kΩ or higher
      F22-2 (SS2) - F8-17 (SSW2) Always Below 1 Ω
      F22-2 (SS2) - Body ground Always 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Engine Switch)
      *2 Front view of wire harness connector
      (to Power Management Control ECU)

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (ENGINE SWITCH - POWER MANAGEMENT CONTROL ECU OR BODY GROUND) 

    OK → See step   11 

  8. GO TO OTHER FLOW CHART (ROOM OSCILLATOR DOES NOT RECOGNIZE KEY). Refer to  Room Oscillator does not Recognize Key 
  9. REPLACE POWER MANAGEMENT CONTROL ECU. Refer to  REMOVAL 
  10. REPLACE ENGINE SWITCH. Refer to  REMOVAL 
  11. REPLACE POWER MANAGEMENT CONTROL ECU. Refer to  REMOVAL