METER / GAUGE SYSTEM Operating Light Control Rheostat does not Change Light Brightness

DESCRIPTION

w/ Multi-information Display:

When the light control rheostat knob is turned to the left, the combination meter and vehicle interior illumination will become brighter. When the light control rheostat knob is turned to the right, the combination meter and vehicle illumination will dim.

WIRING DIAGRAM

A01X2YWE02

PROCEDURE


  1. READ VALUE USING INTELLIGENT TESTER (LIGHT CONTROL RHEOSTAT)


    1. Operate the intelligent tester according to the display and select 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 right (0) → fully turned left (100) Unit: %

      Tech Tips

      *: w/ TAIL Cancel Switch

      OK
      Light brightness can be changed within specified range by manual operation.

    OK

    REPLACE COMBINATION METER ASSEMBLY Click here

    NG

  2. INSPECT LIGHT CONTROL RHEOSTAT


    1. Inspect the light control rheostat.

      A01WZT4E04

      1. Remove the light control rheostat Click here.

      2. Measure the resistance according to the table below.

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

    2. Inspect the trip switch.


      1. Measure the resistance according to the table below.

        Standard Resistance
        Tester Connection Switch Condition Specified Condition
        4 (A/B) - 1 (E) TRIP switch on (Pushed) Below 200 Ω
        TRIP switch off (Not Pushed) 1 MΩ or higher

    NG

    REPLACE LIGHT CONTROL RHEOSTAT Click here

    OK

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

    A01X0AZE02
    *1 Rear view of wire harness connector: (to Combination Meter Assembly)
    *2 Rear view of wire harness connector: (to Light Control Rheostat)

    1. Disconnect the E8 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
      E8-18 (ILL+) - E9-5 (T) Always Below 1 Ω
      E8-19 (TR) - E9-7 (TR)
      E8-23 (E2) - E9-1 (E)
      E8-20 (TC) - E9-6 (TC)

    OK

    REPLACE COMBINATION METER ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR