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

HINT
* The meter illumination level can be adjusted by operating the light control rheostat.
* The meter illumination dims when the light control switch is turned to the tail, head, or AUTO position at night.
* Setting the meter illumination to maximum brightness cancels the above dimming of the meter illumination.
* Setting the meter illumination to minimum brightness almost turns off (very dim) the meter illumination when the light control switch is changed to the tail, head, or AUTO position at night.

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. SYSTEM CHECK

(a) Confirm the symptoms.

Result:





B -- READ VALUE USING TECHSTREAM (TAIL CANCEL SW)
A -- Continue to next step.

2. READ VALUE USING TECHSTREAM (RHEOSTAT VALUE)

(a) Connect the Techstream to the DLC3.

(b) Turn the power 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 gradually changes with actual rheostat knob operation.

NG -- INSPECT LIGHT CONTROL RHEOSTAT

OK -- REPLACE METER CIRCUIT PLATE Disassembly

3. INSPECT LIGHT CONTROL RHEOSTAT

(a) Remove the light control rheostat Removal.





(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 SUB-ASSEMBLY - LIGHT CONTROL RHEOSTAT)

(a) Disconnect the L27 and L59 connectors.

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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE METER CIRCUIT PLATE Disassembly

5. READ VALUE USING TECHSTREAM (TAIL CANCEL SW)

(a) Connect the Techstream to the DLC3.

(b) Turn the power 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





HINT
The tail cancel switch is operated by turning the light control rheostat knob fully upward.

OK:

Condition displayed on the Techstream is the same as the actual light control rheostat knob position.

NG -- INSPECT LIGHT CONTROL RHEOSTAT

OK -- REPLACE METER CIRCUIT PLATE Disassembly

6. INSPECT LIGHT CONTROL RHEOSTAT

(a) Remove the light control rheostat Removal.





(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.

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

(a) Disconnect the L27 and L59 connectors.

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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE METER CIRCUIT PLATE Disassembly