Instrument Cluster Illumination, Location/Function

Instrument cluster display illumination
The instrument cluster (A1) lighting is switched on automatically when the instrument cluster is activated.
The instrument cluster is activated, for example, by opening the driver's door or by pressing the reset button (A1s3).

The brightness of the illumination depends on:
- the surrounding brightness
- the status of terminal 58K (side lights ON/OFF)
- the setting of the instrument and search illumination rheostat (A1r1)

Brightness of the display illumination when the side lights are ON (term. 58K ON)
A distinction is made between two possible cases which depend on the ambient brightness measured by the phototransistor (p):
- The phototransistor controls the brightness of the display above a defined threshold of ambient brightness. The brightness of the display increases as the ambient brightness increases. The setting of the instrument and search illumination rheostat (A1r1) is of no significance.
- Below the threshold, the brightness of the display depends on the ambient brightness and on the setting of the instrument and search illumination rheostat (A1r1). In this case the larger value applies.

Brightness of the display illumination when the side lights are OFF (term. 58K OFF)
The brightness of the display depends entirely on the ambient brightness measured by the phototransistor. The brightness of the display can range from the threshold value to the maximum brightness.
The setting of the instrument and search illumination rheostat (A1r1) is of no significance.


NOTE: If the ambient brightness changes, the display brightness changes after approximately 3 seconds.