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Back-up Light Circuit [08/2019 - ]: Procedure

  1. CHECK FOR DTC 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.
    5. Check for DTCs.

      Powertrain > Hybrid Control > Trouble Codes 

      Result

      Result Proceed to
      Hybrid control system DTCs are not output A
      Hybrid control system DTCs are output B

    Result: 

    B 

    GO TO HYBRID CONTROL SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2015 - ] 

    Result: 

    A 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - BODY GROUND) 
    1. Disconnect the 2B 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
      2B-3 - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU ASSEMBLY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY) 
    1. Disconnect the A40 hybrid vehicle control ECU assembly 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
      A40-2 (BL) - 2C-19 Always Below 1 Ω
      A40-2 (BL) or 2C-19 - 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 HYBRID VEHICLE CONTROL ECU ASSEMBLY (OUTPUT VOLTAGE) 
    GTY959589Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Component with harness connected
    (Instrument Panel Junction Block Assembly)
    1. Connect the A40 hybrid vehicle control ECU assembly connector.
    2. Connect the 2B and 2C instrument panel junction block assembly connectors.
    3. Measure the voltage according to the value (s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      2C-19 - Body ground Power switch off, reverse (R) not selected Below 1 V
      2C-19 - Body ground Power switch on (IG), reverse (R) selected 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE HYBRID VEHICLE CONTROL ECU ASSEMBLY. Refer to  REMOVAL [08/2019 - ] 

    Result: 

    OK 

    See step  5

  5. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (OUTPUT VOLTAGE) 
    GTY959590Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Component with harness connected
    (Instrument Panel Junction Block Assembly)
    1. Measure the voltage according to the value (s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      2D-10 - Body ground Power switch off, reverse (R) not selected Below 1 V
      2D-10 - Body ground Power switch on (IG), reverse (R) selected 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    NG 

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY. Refer to  REMOVAL [08/2019 - ] 

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