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Power Source Mode does not Change to ON (IG) [06/2015 - ]: Procedure

  1. CHECK FOR DTC 
    1. Using the Techstream, check for DTCs.

      Body Electrical > Power Source Control > Trouble Codes 

      Body Electrical > Smart Key > Trouble Codes 

      Result

      Result Proceed to
      DTCs are not output A
      Smart key system (for Start Function) DTCs are output B

    Result: 

    B 

    GO TO DIAGNOSTIC TROUBLE CODE CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART [06/2015 - ] 

    Result: 

    A 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY) 
    1. Disconnect the G40 certification ECU (smart key ECU assembly) connector.
    2. Disconnect the 4A and 4B instrument panel junction block assembly connectors.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      G40-3 (IG1D) - 4A-40 Always Below 1 Ω
      4B-7 - Body ground Always Below 1 Ω
      G40-3 (IG1D) or 4A-40 - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - NO. 1 INTEGRATION RELAY) 
    1. Disconnect the 4C certification ECU (smart key ECU assembly) connector.
    2. Disconnect the 1B No. 1 integration relay connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      4C-11 - 1B-2 Always Below 1 Ω
      1B-3 - Body ground Always Below 1 Ω
      4C-11 or 1B-2 - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - IG1 NO. 5 RELAY) 
    1. Disconnect the 4C instrument panel junction block assembly connector.
    2. Remove the IG1 NO. 5 relay from No. 3 motor compartment relay block.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      4C-22 - 1 (IG1 NO. 5 relay) Always Below 1 Ω
      2 (IG1 NO. 5 relay) - Body ground Always Below 1 Ω
      4C-22 or 1 (IG1 NO. 5 relay) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  5

  5. CHECK INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (IG1 NO. 1, IG1 NO. 2, IG1 NO. 3 RELAY) 
    1. Remove the instrument panel junction block assembly.

      Refer to REMOVAL [06/2015 - 11/2018] , or refer to REMOVAL [11/2018 - ]

    2. Measure the resistance according to the value(s) in the table below.
      GTY573491Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component without harness connected
      (Instrument Panel Junction Block Assembly)      		 - -

      Standard Resistance

      Tester Connection Condition Specified Condition
      4A-40 - 4B-7 20°C (68°F) 87.32 to 127.14 Ω
      4E-1 - 4D-6 Auxiliary battery voltage applied to terminals 4A-40 and 4B-7 Below 1 Ω
      Auxiliary battery voltage not applied to terminals 4A-40 and 4B-7 10 kΩ or higher
      4K-1 - 4F-7 Auxiliary battery voltage applied to terminals 4A-40 and 4B-7 Below 1 Ω
      Auxiliary battery voltage not applied to terminals 4A-40 and 4B-7 10 kΩ or higher
      4K-1 - 4F-9 Auxiliary battery voltage applied to terminals 4A-40 and 4B-7 Below 1 Ω
      Auxiliary battery voltage not applied to terminals 4A-40 and 4B-7 10 kΩ or higher
      4A-40 - 4C-11 Always Below 1 Ω
      4A-40 - 4C-22 Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY. Refer to  REMOVAL [06/2015 - 11/2018]  , or refer to  REMOVAL [11/2018 - ] 

    Result: 

    OK 

    See step  6

  6. INSPECT IG1 NO. 5 RELAY 
    1. Remove the IG1 NO. 5 relay from No. 3 motor compartment relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      3 - 5 Auxiliary battery voltage applied to terminals 1 and 2 Below 1 Ω
      Auxiliary battery voltage not applied to terminals 1 and 2 10 kΩ or higher
      GTY596784Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 IG1 NO. 5 Relay

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE IG1 NO. 5 RELAY 

    Result: 

    OK 

    See step  7

  7. INSPECT NO. 1 INTEGRATION RELAY 
    1. Remove the No. 1 integration relay.

      Refer to REMOVAL [06/2015 - 11/2018] , or refer to REMOVAL [11/2018 - ]

    2. Inspect the No. 1 integration relay.

      Refer to INSPECTION [06/2015 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE NO. 1 INTEGRATION RELAY. Refer to  REMOVAL [06/2015 - 11/2018]  , or refer to  REMOVAL [11/2018 - ] 

    Result: 

    OK 

    See step  8

  8. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 
    1. Reconnect the certification ECU (smart key ECU assembly) connector.
    2. Install the instrument panel junction block assembly.

      Refer to INSTALLATION [06/2015 - 11/2018] , or refer to INSTALLATION [11/2018 - ]

    3. Install the No. 1 integration relay.

      Refer to INSTALLATION [06/2015 - 11/2018] , or refer to INSTALLATION [11/2018 - ]

    4. Install the IG1 NO. 5 relay.
    5. Measure the voltage according to the value(s) in the table below.
      GTY598376Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Certification ECU (Smart Key ECU Assembly))

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      G40-3 (IG1D) - Body ground Power switch on (ACC) → Power switch on (IG) 1 V or less → 9 V or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [06/2015 - 11/2018]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [11/2018 - ] 

    Result: 

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [06/2015 - 11/2018]  , or refer to  REMOVAL [11/2018 - ] 

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