METER / GAUGE SYSTEM Meter Illumination is Always Dark

DESCRIPTION

This inspection is only for vehicles with automatic light control.

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

Tech Tips


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

  • The meter illumination dims when the light control switch is turned to the tail or head position at night.

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

WIRING DIAGRAM

B001D05E04

PROCEDURE


  1. CHECK CAN COMMUNICATION SYSTEM


    1. Check if a CAN communication DTC is output.


      1. w/ Central Gatway ECU Click here.

      2. w/o Central Gatway ECU Click here.

        Result
        Result Proceed to
        CAN communication DTC is not output. A
        CAN communication system DTC is output (w/ Central Gatway ECU) B
        CAN communication system DTC is output (w/o Central Gatway ECU) C

    B

    GO TO CAN COMMUNICATION SYSTEM w/ Central Gateway ECU Click here w/o Central Gateway ECU Click here

    C

    GO TO CAN COMMUNICATION SYSTEM w/ Central Gateway ECU Click here w/o Central Gateway ECU Click here

    A

  2. CHECK DTC (LIGHT SENSOR CIRCUIT)


    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 for Halogen Headlight Click here for LED Headlight Click here

    A

  3. CHECK OPERATION (HEATER CONTROL PANEL)


    1. Turn the ignition switch to ON.

    2. Turn the light control switch to the tail, head, or AUTO position.

    3. Cover the automatic light control sensor.

    4. Check the heater control panel illumination.

      Result
      Result Proceed to
      Heater control panel illumination does not operate normally. A
      Heater control panel illumination operates normally. B

      Tech Tips

      Both the heater control panel illumination and combination meter assembly illumination dim according to the dimmer signal. Therefore, when only the meter illumination is always dark, there may be a malfunction in the combination meter assembly.


    B

    REPLACE COMBINATION METER ASSEMBLY Click here

    A

  4. CHECK OPERATION (AUTOMATIC LIGHT CONTROL SYSTEM)


    1. Turn the ignition switch to ON.

    2. Turn the light control switch to the AUTO position.

    3. Cover the automatic light control sensor.

    4. Check the taillights and low beam headlights.

      OK
      The taillights and low beam headlights come on.

    5. Uncover the automatic light control sensor.

    6. Check the low beam headlights and taillights.

      OK
      The taillights and low beam headlights go off.
      Result
      Result Proceed to
      Automatic light control system operates normally. A
      Automatic light control system does not operate normally. B

    B

    CHECK LIGHTING SETTING for Halogen Headlight Click here for LED Headlight Click here

    A

  5. REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)


    1. Replace the main body ECU (multiplex network body ECU) with a new or a normal one Click here.

      OK
      The operation of the combination meter assembly returns to normal.

      Tech Tips

      The meter CPU controls the meter illumination based on an auto dimmer signal from the main body ECU (multiplex network body ECU). When the meter illumination is always dark (very dim), it may be due to the main body ECU (multiplex network body ECU) sending an auto dimmer signal to the meter CPU because of a malfunction in the main body ECU (multiplex network body ECU).


    OK

    END (MAIN BODY ECU [MULTIPLEX NETWORK BODY ECU])

    NG

    REPLACE COMBINATION METER ASSEMBLY Click here