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Instrument and display lighting (MIU2)

Instrument and display lighting (MIU 2)

The brightness of certain lamps in the main instrument display panel is controlled by the SID unit via pins 3 and 4. There are three different brightness levels:


Rheostat level

Cabin light level

Display lighting level


Rheostat

The rheostat is connected to the SID unit which sends the rheostat value to pins 3 and 4 of the main instrument display panel. The rheostat also controls the following instrument lighting when it is dark:


Speedometer

Tachometer

Coolant temperature gauge

Fuel gauge

Turbo pressure gauge


Cabin light level

The light sensor is mounted in the SID unit which sends a light intensity signal to pins 3 and 4 of the main instrument display panel.

When light intensity exceeds a certain level, the following instrument lighting will be extinguished:


Speedometer

Tachometer

Coolant temperature gauge

Fuel gauge

Turbo pressure gauge

Similarly, the brightness of the following indicator and warning lamps changes when the light intensity in the cabin drops below a certain level.

Low intensity in the dark and high intensity in daylight.

All these lamps are grounded in the main instrument display panel.

LH direction indicators repeater

RH direction indicators repeater

Main beam

Lights on

Rear fog light

CRUISE

The brightness of the following lamps also changes in daylight and in the dark but they all receive current (+15 circuit) from the main instrument display panel and are grounded in the main instrument display panel's control module:

Fuel warning lamp

INFO DISPL lamp

Central warning lamp


Display lighting

The SID unit calculates a suitable display lighting intensity on the basis of the rheostat value and the light intensity in the cabin, which is obtained from the light sensor.

When it is dark, display lighting is controlled by the rheostat setting and as it gets lighter it is controlled by the light intensity in the cabin.

This ensures that the displays will be easy to read in all conditions of light. The following lamps are controlled by the intensity of the display lighting in the main instrument display panel:


Trip meter

Odometer