Operating Light Control Rheostat Does Not Change Light Brightness
METER: METER / GAUGE SYSTEM: Operating Light Control Rheostat does not Change Light Brightness
Operating Light Control Rheostat does not Change Light Brightness
WIRING DIAGRAM
INSPECTION PROCEDURE
PROCEDURE
1. CHECK ILLUMINATION
(a) Operate the rheostat and check that the quantity of light for the combination meter assembly, audio system and A/C control panel etc. are normally changed.
Result:
B -- INSPECT LIGHT CONTROL RHEOSTAT
A -- Continue to next step.
2. READ VALUE USING INTELLIGENT TESTER
(a) Check the date list of body ECU.
OK -- NORMAL
NG -- Continue to next step.
3. INSPECT LIGHT CONTROL RHEOSTAT
(a) Measure the voltage according to the value(s) in the table below.
Standard voltage:
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- REPLACE LIGHT CONTROL RHEOSTAT
OK -- Continue to next step.
4. CHECK HARNESS AND CONNECTOR
(a) Check the resistance between terminals 8 (TC) of light control rheostat and B5-18 of body ECU connector.
Standard resistance:
Below 1Ohms
(b) Check the resistance between terminals C9-16 of combination meter assembly and B5-5 of body ECU.
Standard resistance:
Below 1Ohms
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE COMBINATION METER ASSEMBLY
5. INSPECT LIGHT CONTROL RHEOSTAT
(a) Measure the voltage according to the value(s) in the table below.
Standard voltage:
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- REPLACE LIGHT CONTROL RHEOSTAT
OK -- Continue to next step.
6. CHECK HARNESS AND CONNECTOR (LIGHT CONTROL RHEOSTAT - INSTRUMENT PANEL JUNCTION BLOCK)
(a) Check the resistance between 1 (T) of light control rheostat and R12-21 of instrument panel junction block assembly.
Standard resistance:
Below 1Ohms
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
7. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY
(a) Measure voltage between terminal R12-21 of instrument panel junction block assembly and body ground.
Standard voltage:
NG -- REPAIR OR REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY
OK -- REPLACE COMBINATION METER ASSEMBLY