Installation manual

System Overview 1-9
BRIGHTNESS CONTROLS
Each IFD has brightness controls to control both the bezel and
the display brightness. The user can access individual controls to
allow for either manual control of brightness, automatic control of
brightness in response to the cockpit dimming controls/rheostats
or automatic control of brightness in response to the ambient light
sensor that is embedded in the bezel. The user accessible
controls for all are on the AUX page using the User Options LSK
of the Setup tab.
Brightness Controls
Depending on how the installer configured the brightness controls
at time of installation, the “Auto” setting will typically revert to the
dimming bus setting in low ambient light conditions.
If the IFD540 appears “inoperative” or non-responsive from a
lighting perspective, check the aircraft instrument lighting rheostat
to ensure it is not set to a night position.