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Rheostat Light Control

Rheostat light control changes instrument cluster, A/C-heater control panel, and clock illumination. Automatic light control sensor varies instrument cluster illumination depending on outside light levels. Tail cancellation refers to turning rheostat light control clockwise beyond moderate position, causing lights to illuminate fully (100 percent) and system to ignore automatic light control sensor. To diagnose system, check symptoms in table. Refer to RHEOSTAT LIGHT CONTROL SYMPTOMS  table.

RHEOSTAT LIGHT CONTROL SYMPTOMS

Symptom Test No.
Brightness Cannot Be Adjusted 1 
Instrument Cluster Brightness Cannot Be Adjusted 2 
Only Instrument Cluster Brightness Can Be Adjusted 3 
Tail Cancellation Does Not Operate On All Illumination 4 
Tail Cancellation Does Not Operate On Only One Illumination 5 
Full Illumination Does Not Occur When Light Strikes Light Control Sensor (1) 6 
(1) Tail cancellation is off, light switch is in AUTO, vehicle is in dark area and light strikes light control sensor.