METER / GAUGE SYSTEM Meter Illumination is Always Dark

DESCRIPTION

In this circuit, the meter CPU receives auto dimmer signals from the main body ECU RH using the BEAN lines. When the meter CPU receives an auto dimmer signal, it dims the meter illumination. The main body ECU RH determines whether it is daytime, twilight, or nighttime based on the waveform transmitted from the automatic light control sensor. If the main body ECU RH determines that it is daytime, the ECU does not send auto dimmer signals. Therefore, the meter illumination (warning and indicator lights) will not dim even if the driver accidentally turns the light control switch to the TAIL or HEAD position in daytime.

WIRING DIAGRAM

A015ZM6E01

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK DTC


    1. Check if DTC B1244 is output Click here.

      Result
      Result Proceed to
      B1244 is not output A
      B1244 is output B

    B

    GO TO LIGHTING SYSTEM Click here

    A

  2. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (DIMMER SIGNAL)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the intelligent tester on.

    4. Turn the light control switch to the TAIL or HEAD position.

    5. Enter the following menus: Body / Body (Main Body ECU RH) / Active Test.

    6. Check the meter illumination.

      Body (Main Body ECU RH)
      Tester Display Test Part Normal Condition Diagnostic Note
      Dimmer Signal Dimmer signal ON or OFF OFF: The meter illumination (warning and indicator lights) will not dim even if the light control switch to the TAIL or HEAD position
      ON: The meter illumination (warning and indicator lights) dim when the light control switch to the TAIL or HEAD position
      OK
      Meter illumination does not dim when turning the light control switch to the TAIL or HEAD position in daytime.

      Tech Tips

      Meter illumination is adjusted by lighting system and controlled according to the outside light. The automatic light control sensor sensitiveness can be customized. Therefore, when the Data List value is normal, confirm the sensitivity setting in the customization table of the automatic light control system Click here.


    NG

    REPLACE COMBINATION METER Click here

    OK

    CHECK LIGHTING SETTING Click here

  3. REPLACE COMBINATION METER


    1. Replace the combination meter with a new or a known good one Click here.

      OK
      The operation of the combination meter returns to normal.

    NG

    REPLACE MAIN BODY ECU RH

    OK

    END