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Headlight Leveling ECU Power Source Circuit [04/2013 - 10/2016]: Procedure

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  1. READ VALUE USING TECHSTREAM 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / HL AutoLeveling / Data List.
    5. Read the display on the Techstream.

      Body Electrical > HL AutoLeveling > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      +B IG power supply voltage value 0.00 to 19.75 V 11.00 to 14.00 V -

      Body Electrical > HL AutoLeveling > Data List 

      Tester Display
      +B

      OK

      Normal condition listed above is displayed.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [04/2013 - 10/2016] 

    Result: 

    NG 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (BATTERY - HEADLIGHT LEVELING ECU ASSEMBLY) 
    1. Disconnect the A65 headlight leveling ECU assembly connector.
      GTY461057Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Headlight Leveling ECU Assembly)
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A65-1 (IG) - Body ground Engine switch on (IG) 11 to 14 V
      A65-1 (IG) - Body ground Engine switch off Below 1 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (HEADLIGHT LEVELING ECU ASSEMBLY - BODY GROUND) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A65-9 (E1) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE HEADLIGHT LEVELING ECU ASSEMBLY. Refer to  REMOVAL [04/2013 - 10/2016] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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