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

  1. CHECK DTC (ALL) See step   1 

    NG → GO TO  DIAGNOSTIC TROUBLE CODE CHART 

    OK: Go to next step 

  2. CHECK HARNESS AND CONNECTOR (BATTERY - POWER SOURCE CONTROL ECU) 
    1. Disconnect the C43 power source control ECU connector.
      Fig 1: Checking Battery - Power Source Control ECU
      GTY313084Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      C43-1 (AM22) - Body ground Always 9.5 to 14 V
      TEXT IN ILLUSTRATION

      *a Rear view of wire harness connector
      (to Power Source Control ECU)

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

    OK: Go to next step 

  3. INSPECT INTEGRATION RELAY (IG2 RELAY) 
    1. Remove the integration relay.
    2. Inspect the integration relay. Refer to ON-VEHICLE INSPECTION .

    NG → REPLACE INTEGRATION RELAY 

    OK: Go to next step 

  4. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (IG1 NO. 1, IG1 NO. 2 AND IG1 NO. 3 RELAYS) 
    1. Disconnect the 2C and 2D instrument panel junction block assembly connectors.
      Fig 2: Inspecting Instrument Panel Junction Block Assembly (IG1 NO. 1, IG1 NO. 2 And IG1 NO. 3 Relays)
      GTY312400Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *a Component without harness connected
      (Instrument Panel Junction Block Assembly)
      - -
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      2C-26 - 2D-9 20°C (68°F) 181.82 to 272.73 Ω

    NG → REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 

    OK: Go to next step 

  5. CHECK HARNESS AND CONNECTOR (POWER SOURCE CONTROL ECU - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY) 
    1. Disconnect the C43 power source control ECU connector.
    2. Disconnect the 2C instrument panel junction block assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      C43-20 (IG1D) - 2C-26 Always Below 1 Ω
      C43-20 (IG1D) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  6. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - BODY GROUND) 
    1. Disconnect the 2D instrument panel junction block assembly connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      2D-9 - Body ground Always Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  7. CHECK HARNESS AND CONNECTOR (POWER SOURCE CONTROL ECU - INTEGRATION RELAY) 
    1. Disconnect the C42 power source control ECU connector.
    2. Disconnect the 1A integration relay connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      C42-8 (IG2D) - 1A-2 Always Below 1 Ω
      C42-8 (IG2D) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  8. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY - BODY GROUND) 
    1. Disconnect the 1A integration relay connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      1A-3 - Body ground Always Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  9. CHECK POWER SOURCE CONTROL ECU See step   3 

    NG → See step   11 

    OK → See step   10 

  10. USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING 
  11. REPLACE POWER SOURCE CONTROL ECU. Refer to  REMOVAL