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Headlight Signal Circuit [10/2013 - ]: Procedure

WARNING: This page is about a different variant/trim than selected.
  1. READ VALUE USING TECHSTREAM 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / HL Auto Leveling / Data List.
    5. Read the display on the Techstream.
      HL AUTO LEVELING

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Headlight Low Beam State Low beam headlight state/ON or OFF ON: Low beam headlights on
      OFF: Low beam headlights off
      -

      OK

      Normal conditions listed above are displayed.

    NG → See step   2 

    OK → See step   4 

  2. CHECK HARNESS AND CONNECTOR (HEADLIGHT LEVELING ECU ASSEMBLY) 
    1. Disconnect the A96 headlight leveling ECU assembly connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A96-3 (HDLP) - Body ground Low beam headlights on Below 1.5 V
      Low beam headlights off 5 V or higher

    NG → See step   3 

    OK → See step   5 

  3. CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - HEADLIGHT LEVELING ECU ASSEMBLY) 
    1. Disconnect the No. 1 integration relay connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      1G-11 (HL4B) - A96-3 (HDLP) Always Below 1 Ω
      1G-11 (HL4B) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   6 

  4. PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [10/2013 - ] 
  5. REPLACE HEADLIGHT LEVELING ECU ASSEMBLY. Refer to  REMOVAL [10/2013 - ] 
  6. REPLACE NO. 1 INTEGRATION RELAY. Refer to  REMOVAL [10/2013 - ]