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Instrument Panel, Gauges and Warning Indicators: Description and Operation





Instrument Cluster and Panel Illumination

COMPONENT LOCATION









INTRODUCTION
Instrument cluster and panel illumination is achieved through a series of Light Emitting Diodes (LED's) located throughout the interior of the vehicle. The intensity of illumination can be controlled by the driver through a rotary control located on the lower drivers side of the instrument panel. The rotary control is integral with the auxiliary lighting switch.
The rotary control is a variable resistor which is used as a potential divider to provide a high or low voltage according to its set position. The voltage returned to the instrument cluster is converted into a dimmer control positional message and transmitted to the CJB over the medium speed Controller Area Network (CAN) bus. The CJB converts the illumination intensity message into a Pulse Width Modulation (PWM) signal which it supplies to the instrument panel and switch illumination LED.

CONTROL DIAGRAM

NOTE:
A = Hardwired; N = Medium speed CAN bus