METER / GAUGE SYSTEM Meter Illumination does not Dim at Night

DESCRIPTION

If the dimmer switch is turned to tail, head or AUTO, the main body ECU sends a TAIL relay signal, panel light illumination signal, panel relay signal, and TAIL cancel OFF signal to the combination meter. Then the meter and accessory meter become dim.

Tech Tips

TAIL cancel switch: When the headlights are illuminated and the TAIL cancel switch is turned off, the meter does not dim.

WIRING DIAGRAM

A01WPHWE01

PROCEDURE


  1. CHECK CAN COMMUNICATION SYSTEM


    1. Check for DTCs.


      Result
      Result Proceed to
      CAN communication system DTC is not output A
      CAN communication system (for LHD) DTC is output B
      CAN communication system (for RHD) DTC is output C

    B

    GO TO CAN COMMUNICATION SYSTEM Click here

    C

    GO TO CAN COMMUNICATION SYSTEM Click here

    A

  2. READ VALUE DATA LIST USING GTS


    1. Operate the GTS according to the display and select the Data List Click here.

      Combination Meter
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Tail Cancel SW TAIL cancel switch condition/ON or OFF

      ON: TAIL cancel switch on

      OFF: TAIL cancel switch off

      		 -
      Rheostat value Light control rheostat switch input/Min.: 0, Max.: 100 Light control rheostat switch is fully turned left (0) → fully turned right (100) Unit: %
      OK
      Light brightness can be changed within specified range by manual operation.

    NG

    REPLACE COMBINATION METER ASSEMBLY Click here

    OK

  3. INSPECT LIGHT CONTROL RHEOSTAT


    1. Inspect the light control rheostat.

      A01WU7RE01

      1. Remove the light control rheostat Click here.

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

        Standard Resistance
        Tester Connection Switch Condition Specified Condition
        6 (TC) - 5 (T) TAIL cancel switch off → on 10 kΩ or higher → Below 1 Ω
        5 (T) - 1 (E) Always 10 kΩ +/-20%
        7 (TR) - 1 (E) Light control rheostat fully turned right → fully turned left 10 kΩ +/-20% → Below 100 Ω

    NG

    REPLACE LIGHT CONTROL RHEOSTAT Click here

    OK

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


    1. Disconnect the E120 meter connector.

    2. Disconnect the E9 rheostat connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      E120-30 (ILL+) - E9-5 (T) Always Below 1 Ω
      E120-31 (TR) - E9-7 (TR)
      E120-19 (E2) - E9-1 (E)
      E120-32 (TC) - E9-6 (TC)
      E120-30 (ILL+) or E9-5 (T) - Body ground Always 10 kΩ or higher
      E120-31 (TR) or E9-7 (TR) - Body ground
      E120-19 (E2) or E9-1 (E) - Body ground
      E120-31 (TC) or E9-6 (TC) - Body ground

    OK

    REPLACE COMBINATION METER ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR