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Headlight Beam Level Control Actuator Circuit: Procedure

  1. PERFORM ACTIVE TEST USING TECHSTREAM 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (READY).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / HL Auto Leveling / Active Test.
    5. Check that the leveling motors operate.
      HL AUTO LEVELING

      Tester Display Test Part Control Range Diagnostic Note
      Drive The Leveling Motor UP Leveling motor upward operation ON/OFF ON: Move up
      OFF: Stop
      Drive The Leveling Motor DOWN Leveling motor downward operation ON/OFF ON: Move down
      OFF: Stop

      OK

      Headlight leveling motors operate normally.

    NG → See step   2 

    OK → See step   5 

  2. CHECK HARNESS AND CONNECTOR (HEADLIGHT LEVELING MOTOR - HEADLIGHT LEVELING ECU ASSEMBLY) 
    1. Disconnect the A96 headlight leveling ECU assembly connector.
    2. Disconnect the A87 or A99 headlight unit (headlight leveling motor) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      LH SIDE

      Tester Connection Condition Specified Condition
      A96-18 (LHT) - A87-2 (LH T) Always Below 1 Ω
      A96-11 (LH+) - A87-3 (LHIG) Always Below 1 Ω
      A96-24 (LH-) - A87-1 (LH E) Always Below 1 Ω
      A96-18 (LHT) - Body ground Always 10 kΩ or higher
      A96-11 (LH+) - Body ground Always 10 kΩ or higher
      A96-24 (LH-) - Body ground Always 10 kΩ or higher
      RH SIDE

      Tester Connection Condition Specified Condition
      A96-17 (RHT) - A99-2 (RH T) Always Below 1 Ω
      A96-10 (RH+) - A99-3 (RHIG) Always Below 1 Ω
      A96-23 (RH-) - A99-1 (RH E) Always Below 1 Ω
      A96-17 (RHT) - Body ground Always 10 kΩ or higher
      A96-10 (RH+) - Body ground Always 10 kΩ or higher
      A96-23 (RH-) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  3. CHECK HEADLIGHT UNIT (HEADLIGHT LEVELING MOTOR) 
    1. Replace the headlight unit (headlight leveling motor) with a new or a known good one. Refer to REMOVAL .
    2. Perform the active test of the leveling motors.

      OK

      Headlight leveling motors operate normally.

    NG → See step   4 

    OK → END (HEADLIGHT UNIT (HEADLIGHT LEVELING MOTOR) WAS DEFECTIVE) 

  4. REPLACE HEADLIGHT LEVELING ECU ASSEMBLY. Refer to  REMOVAL 
  5. PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE