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 switch in the trip switch.

WIRING DIAGRAM

B004YQME04

CAUTION / NOTICE / HINT

Note

When replacing the combination meter assembly, always replace it with a new one. If a combination meter assembly which was installed to another vehicle is used, the information stored in it will not match the information from the vehicle and a DTC may be stored.

Tech Tips


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


  • The meter illumination dims when the taillights are turned on.


  • Setting the meter illumination level to maximum brightness cancels the above dimming of the meter illumination.

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: Switch released

      ON: Switch pressed

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

      OFF: Switch released

      ON: 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. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - TRIP SWITCH)


    1. Disconnect the G34 combination meter assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G34-25 (TR) - G8-5 (RV) Always Below 1 Ω
      G34-26 (SW3) - G8-7 (E) Always Below 1 Ω
      G34-25 (TR) or G8-5 (RV) - Other terminals and body ground Always 10 kΩ or higher
      G34-26 (SW3) or G8-7 (E) - Other terminals and body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. INSPECT TRIP SWITCH


    1. Temporarily replace the trip switch with a new or normally functioning one.

      Click here

      Result
      Proceed to
      OK
      NG

    OK

    REPLACE COMBINATION METER ASSEMBLY Click here

    NG

    REPLACE TRIP SWITCH Click here