METER / GAUGE SYSTEM Operating Light Control Rheostat does not Change Light Brightness

DESCRIPTION

The combination meter assembly receives signals from this circuit to adjust the illumination of the combination meter assembly. The combination meter assembly sets the illumination level based on the user operation of the light control rheostat.

WIRING DIAGRAM

A01MFK0E04

CAUTION / NOTICE / HINT

Note

When replacing the combination meter assembly, make sure to replace it with a new one.

Tech Tips

The meter illumination level can be adjusted by pressing the light control rheostat switch.

PROCEDURE


  1. READ VALUE USING GTS (LIGHT CONTROL UP SWITCH, LIGHT CONTROL DOWN SWITCH)


    1. Using the GTS, read the Data List.

      Click here


      Body Electrical > Combination Meter > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Light Control Up Switch Light control rheostat up switch OFF or ON

      OFF: Light control rheostat up switch released

      ON: Light control rheostat up switch pressed

      		 -
      Light Control Down Switch Light control rheostat down switch OFF or ON

      OFF: Light control rheostat down switch released

      ON: Light control rheostat down switch pressed

      		 -

      Body Electrical > Combination Meter > Data List
      Tester Display
      Light Control Up Switch
      Light Control Down Switch
      OK
      Light control rheostat up or down switch condition displayed on the GTS changes with the actual switch operation.
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE COMBINATION METER ASSEMBLY Click here

    NG

  2. INSPECT LIGHT CONTROL RHEOSTAT


    1. Remove the light control rheostat.

      Click here

    2. Inspect the light control rheostat.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE LIGHT CONTROL RHEOSTAT Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - LIGHT CONTROL RHEOSTAT)


    1. Disconnect the G13 combination meter assembly connector.

    2. Disconnect the G12 light control rheostat.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G13-24 (TR) -G12-3 (UP) Always Below 1 Ω
      G13-25 (TC) -G12-2 (DOWN) Always Below 1 Ω
      G13-24 (TR) or G12-3 (UP) - Body ground Always 10 kΩ or higher
      G13-25 (SW3) or G12-2 (DOWN) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE COMBINATION METER ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR