LIGHTING SYSTEM Vehicle Speed Signal Circuit

DESCRIPTION

The headlight leveling ECU receives the vehicle speed signal from the combination meter.

WIRING DIAGRAM

A015BTXE05

INSPECTION PROCEDURE

Note

After replacing the headlight leveling ECU, initialization of the ECU is necessary Click here.

PROCEDURE


  1. READ VALUE USING INTELLIGENT TESTER (VEHICLE SPEED)


    1. Using the intelligent tester, read the Data List Click here.

      HL Auto Leveling (w/ Static Headlight Auto Leveling)
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Vehicle Speed Vehicle speed / 0 to 327.67 km/h Actual vehicle speed -
      OK
      The display is as specified in the normal condition column.

    NG
    OK
  2. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - HEADLIGHT LEVELING ECU ASSEMBLY)


    1. Disconnect the E7 combination meter connector.

    2. Disconnect the E109 headlight leveling ECU connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      E7-4 (+S) - E109-16 (SPDR) Always Below 1 Ω
      E7-4 (+S) - Body ground Always 10 kΩ or higher

    NG
    OK
  3. CHECK COMBINATION METER ASSEMBLY


    1. w/ Multi-information Display:


      1. A0155P7E01
        Text in Illustration
        *a

        Component with harness connected

        (Combination Meter Assembly)

        Remove the combination meter with its connector still connected Click here.

    2. w/o Multi-information Display:


      1. Remove the combination meter with its connector still connected Click here.

    3. Connect an oscilloscope to the combination meter connector.

    4. Check the waveform.

      Measurement Condition
      Item Content
      Terminal No. (Symbol) E7-4 (+S) - Body ground
      Tool setting 5 V/DIV., 20 ms./DIV.
      Condition Vehicle is driven at approximately 20 km/h (12 mph)
      OK
      Waveform is as shown in the illustration.

      Tech Tips

      When the system is functioning normally, one wheel revolution generates 4 pulses. As the vehicle speed increases, the width indicated by (A) in the illustration narrows.


    NG
    OK