METER / GAUGE SYSTEM Meter Illumination does not Dim at Night

DTC Code DTC Name
Meter Illumination does not Dim at Night

DESCRIPTION

In this circuit, the combination meter assembly receives auto dimmer signals from the main body ECU (multiplex network body ECU) using the CAN communication system. When the combination meter assembly receives an auto dimmer signal, it dims the meter illumination (warning and indicator lights).

The main body ECU (multiplex network body ECU) determines whether it is daytime or nighttime based on the waveform transmitted from the automatic light control sensor. If the main body ECU (multiplex network body ECU) determines that it is nighttime and the headlight dimmer switch assembly is in the tail, head, or AUTO position, the ECU sends an auto dimmer signal to the combination meter assembly.

According to this signal, the combination meter assembly dims the meter illumination.

Tip:

When the meter illumination does not dim at night, there may be a malfunction in the automatic light control sensor, main body ECU (multiplex network body ECU), CAN communication system, wire harness, connector, or combination meter assembly.

WIRING DIAGRAM

E143765E86

CAUTION / NOTICE / HINT

Tip:

  • The automatic light control sensor sensitivity can be customized.

    Click here

  • Setting the meter illumination to maximum brightness prevents the meter illumination from dimming when the headlight dimmer switch assembly is changed to the tail, head, or AUTO position at night. Therefore, check the meter illumination setting before proceeding to the following steps.

  • Before starting the following inspection, check if lighting system DTCs are output.

    Click hereClick here

PROCEDURE

  1. CHECK CAN COMMUNICATION SYSTEM

    1. Check if CAN communication DTCs are output.

      Click hereClick hereClick here

    Result

    Result

    Proceed to

    CAN communication DTCs are not output.

    A

    CAN communication DTCs are output.

    B
    B

    GO TO CAN COMMUNICATION SYSTEM

    Click here

    A

  2. READ VALUE USING GTS (ILLUMINATION RATE INFO)

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / Main Body / Data List.

    5. Check the values by referring to the table below.

      Body Electrical > Main Body > Data List

      Tester Display

      Measurement Item

      Range

      Normal Condition

      Diagnostic Note

      Illumination Rate Info

      Illumination rate information

      0.00 ms. to 2162.65 ms.

      Value output according to ambient light levels

      -

      Body Electrical > Main Body > Data List

      Tester Display

      Illumination Rate Info

    Result

    Result

    Proceed to

    The output value changes according to the ambient light level.

    A

    The output value does not change according to the ambient light level.

    B
    B

    CHECK CUSTOMIZE PARAMETER SETTING (SENSITIVITY)

    Click here

    A

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

    1. Replace the main body ECU (multiplex network body ECU) with a new or known good one.

      for LHD:Click here

      for RHD:Click here

      OK

      The operation of the combination meter assembly returns to normal.

      Tip:

      The combination meter assembly controls the meter illumination based on an auto dimmer signal from the main body ECU (multiplex network body ECU). If the combination meter assembly does not dim when the headlight dimmer switch assembly is in the tail, head, or AUTO position at night, it may be for one of 2 reasons. The first reason is that the main body ECU (multiplex network body ECU) did not send an auto dimmer signal. The second is that the combination meter assembly did not dim the meter illumination even though the combination meter assembly received an auto dimmer signal.

    Result

    Proceed to

    OK

    NG
    OK

    END

    NG

    REPLACE COMBINATION METER ASSEMBLY

    for Hatchback, Wagon:Click here

    for Sedan:Click here