Operating Light Control Rheostat Does Not Change Light Brightness

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

DESCRIPTION

The meter CPU receives signals from this circuit to adjust the illumination of the meter, instrument panel, accessory meter assembly and headup display. The meter CPU sets the illumination level based on the user operation of the light control rheostat up or down switches.

HINT
* The meter illumination level can be adjusted by pressing the light control rheostat up or down switches.
* 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.
* Setting the meter illumination to maximum brightness turns off the meter illumination when the light control switch is changed to the tail or head position.
* The whole light control switch should be replaced if the ODO/TRIP switch is malfunctioning.

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. SYSTEM CHECK

(a) Confirm the symptoms.

Result:





B -- INSPECT LIGHT CONTROL RHEOSTAT
A -- Continue to next step.

2. READ VALUE USING TECHSTREAM (LIGHT CONTROL UP SW, LIGHT CONTROL DOWN SW)

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / Combination Meter / Data List.

(e) Check the values by referring to the table below.

Combination Meter





OK:

The value displayed on the Techstream changes with the actual rheostat switch operation.

NG -- INSPECT LIGHT CONTROL RHEOSTAT

OK -- REPLACE COMBINATION METER ASSEMBLY Removal

3. INSPECT LIGHT CONTROL RHEOSTAT

(a) Remove the light control rheostat.





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

Standard Resistance:





Text in Illustration





NG -- REPLACE LIGHT CONTROL RHEOSTAT Removal
OK -- Continue to next step.

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

(a) Disconnect the F16 and F6 connectors.





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

Standard Resistance:





Text in Illustration





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE COMBINATION METER ASSEMBLY Removal

5. INSPECT LIGHT CONTROL RHEOSTAT

(a) Remove the light control rheostat.





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

Standard Resistance:





Text in Illustration





NG -- REPLACE LIGHT CONTROL RHEOSTAT Removal
OK -- Continue to next step.

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

(a) Disconnect the F16 and F6 connectors.





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

Standard Resistance:





Text in Illustration





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE COMBINATION METER ASSEMBLY Removal