Instrument cluster illumination, function - GF54.30-P-2007R

MODEL 230

Instrument cluster illumination

The instrument cluster (A1) illumination is switched on automatically when the instrument cluster is activated. Because it relies on black-screen technology, the details on the instrument cluster (e.g. displays, gauges, etc.) now become clearly visible.

The instrument cluster is activated by opening the driver's door, for example, or by pressing the reset button.

The brightness of the illumination depends on:

The ambient brightness and
The setting of the instrument illumination dimmer and reset button (A1r1)

The diagram outlines the relationship between the brightness of the instrument cluster illumination and the ambient brightness and the setting of the instrument illumination dimmer and reset button (A1r1):

Fig 1: Instrument Cluster Illumination Function Graph

Courtesy of MERCEDES-BENZ USA

On curve (a) the instrument illumination dimmer and reset button (A1r1) is set all the way to the right (maximum). As the ambient brightness increases, so does the brightness of the instrument cluster illumination. The possible brightness ranges from (amin) to the maximum value (max) .
On curve (b) the instrument illumination dimmer and reset button (A1r1) is set all the way to the left (minimum). As the ambient brightness increases, so does the brightness of the instrument cluster illumination. The possible brightness ranges from (bmin) to the maximum value (max) . The maximum value (max) , however, is only reached when the ambient brightness is greater.

When the instrument cluster (A1) is activated, the illumination is always set to at least the minimum level (bmin) . The brightness cannot fall below this minimum level.

As is evident from the diagram, changing the instrument illumination dimmer and reset button (A1r1) also changes the minimum value from (amin) to (bmin) or vice versa.

Phototransistor

The instrument cluster (A1) is equipped with two phototransistors to allow the illumination to be adjusted automatically according to the ambient brightness. The resulting illumination brightness corresponds to the mean value from the measurement of both transistors.

	Activating instrument cluster, function		GF54.30-P-2006R
	Adjusting switch and controls illumination, function		GF54.30-P-2010R
	Instrument cluster (IC), location / task		GF54.30-P-3039R