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Power Source Mode does not Change (08/2011 - ): Procedure

  1. CHECK DTC OUTPUT 
    1. Check whether DTC is output. Refer to DTC CHECK / CLEAR .
      RESULT

      Display (DTC output) Proceed to
      No DTC output A
      DTC output B

    B → See step   15 

    A: Go to next step 

  2. CHECK SMART ACCESS SYSTEM WITH PUSH-BUTTON START 
    Fig 1: Identifying Engine Switch
    GTY108805Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the battery of the electrical key transmitter. Refer to REPLACEMENT .
    2. With the brake pedal depressed, touch the LEXUS mark of the key to the engine switch.
    3. When operating the engine switch, check whether the engine switch changes to on (ACC) or on (IG).

      HINT: 

      • When the electrical key transmitter cannot be verified even when it is in the operational area, the engine start check can be performed by removing the transmitter battery from the electrical key transmitter and holding the transmitter against the engine switch.
      • When performing the check, if the engine switch turns on (ACC) or on (IG), there is a problem with key certification inside the cabin.
      RESULT

      Result Proceed to
      Does not change to on (ACC) A
      Does not change to on (IG) B
      Does not change to on (ACC) and on (IG) C
      Changes to on (ACC) and on (IG) D

    B → See step   5 

    C → See step   11 

    D → See step   16 

    A: Go to next step 

  3. INSPECT FUSE (AM2) 
    1. Remove the AM2 fuse from the engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      AM2 fuse Always Below 1 Ω

    NG → REPLACE FUSE 

    OK: Go to next step 

  4. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - BATTERY AND BODY GROUND) 
    Fig 2: Identifying Main Body ECU Connector Terminal Identification
    GTY359989Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the E1, E2, 2A and 2D main body ECU connectors.
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      E1-6 (AM1) - Body ground Always 11 to 14 V
      E2-1 (AM2) - Body ground Always 11 to 14 V
      2A-1 - Body ground Always 11 to 14 V

      Standard Resistance

      Tester Connection Condition Specified Condition
      E1-22 (ACCD) - 2D-45 Always Below 1 Ω
      2D-62 (GND2) - Body ground Always Below 1 Ω
      E1-22 (ACCD) or 2D-45 - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH) 

  5. INSPECT FUSE (AM2) 
    1. Remove the AM2 fuse from the engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      AM2 fuse Always Below 1 Ω

    NG → REPLACE FUSE 

    OK: Go to next step 

  6. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - BATTERY AND BODY GROUND) 
    Fig 3: Identifying Main Body ECU Connector Terminal Identification
    GTY359127Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the E1, E2, 2A and 2D main body ECU connectors.
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      E1-6 (AM1) - Body ground Always 11 to 14 V
      E2-1 (AM2) - Body ground Always 11 to 14 V
      2A-1 - Body ground Always 11 to 14 V

      Standard Resistance

      Tester Connection Condition Specified Condition
      E1-3 (IG1D) - 2D-43 Always Below 1 Ω
      2D-62 (GND2) - Body ground Always Below 1 Ω
      E1-3 (IG1D) or 2D-43 - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  7. INSPECT INTEGRATION NO. 1 RELAY (IG2 RELAY) 
    Fig 4: Identifying Integration Relay
    GTY138313Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the integration relay from the engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      1B-8 - 1C-1 Battery voltage applied to terminals 1B-6 and 1B-7 Below 1 Ω
      1B-8 - 1C-1 Battery voltage not applied to terminals 1B-6 and 1B-7 10 kΩ or higher

    NG → REPLACE INTEGRATION NO. 1 RELAY 

    OK: Go to next step 

  8. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY (IG2 RELAY) - MAIN BODY ECU AND BODY GROUND) 
    Fig 5: Identifying Integration Relay Connector And Main Body ECU Connector
    GTY125914Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the E2 main body ECU connector.
    2. Disconnect the 1B integration relay connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      E2-11 (IG2D) - 1B-6 Always Below 1 Ω
      1B-7 - Body ground Always Below 1 Ω
      E2-11 (IG2D) or 1B-6 - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  9. INSPECT FUSE (IGN, IG2 MAIN) 
    1. Remove the IGN and IG2 MAIN fuses from the engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      IGN fuse Always Below 1 Ω
      IG2 MAIN fuse Always Below 1 Ω

    NG → REPLACE FUSE 

    OK: Go to next step 

  10. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY (IG2 RELAY) - STEERING LOCK ECU AND BATTERY) 
    Fig 6: Identifying Integration Relay Connector And Steering Lock ECU Connector
    GTY351727Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the E26 steering lock ECU connector.
    2. Disconnect the 1B and 1C integration relay connectors.
    3. Measure the voltage and resistance according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      1C-1 - Body ground Always 11 to 14 V

      Standard Resistance

      Tester Connection Condition Specified Condition
      E26-6 (IG2) - 1B-8 Always Below 1 Ω
      E26-6 (IG2) or 1B-8 - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH) 

  11. INSPECT FUSE (AM2) 
    1. Remove the AM2 fuse from the engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      AM2 fuse Always Below 1 Ω

    NG → REPLACE FUSE 

    OK: Go to next step 

  12. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - BATTERY AND BODY GROUND) 
    Fig 7: Identifying Main Body ECU Connectors
    GTY141159Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the E1, E2 and 2D main body ECU connectors.
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      E1-6 (AM1) - Body ground Always 11 to 14 V
      E2-1 (AM2) - Body ground Always 11 to 14 V

      Standard Resistance

      Tester Connection Condition Specified Condition
      2D-62 (GND2) - Body ground Always Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  13. INSPECT ENGINE SWITCH 
    Fig 8: Identifying Engine Switch Connector
    GTY109967Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the E18 engine switch connector.
    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) 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

    NG → See step   17 

    OK: Go to next step 

  14. CHECK HARNESS AND CONNECTOR (ENGINE SWITCH - MAIN BODY ECU AND BODY GROUND) 
    Fig 9: Identifying Engine Switch Connector Terminal And Main Body ECU Connector Terminal
    GTY110164Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the E1 main body ECU connector.
    2. Disconnect the E18 engine switch connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      E1-17 (SSW1) - E18-7 (SS1) Always Below 1 Ω
      E1-16 (SSW2) - E18-2 (SS2) Always Below 1 Ω
      E18-5 (GND) - Body ground Always Below 1 Ω
      E1-17 (SSW1) or E18-7 (SS1) - Body ground Always 10 kΩ or higher
      E1-16 (SSW2) or E18-2 (SS2) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH) 

  15. GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START (FOR START FUNCTION) (DIAGNOSTIC TROUBLE CODE CHART). Refer to  DIAGNOSTIC TROUBLE CODE CHART 
  16. 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 
  17. REPLACE ENGINE SWITCH. Refer to  REMOVAL 
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