Brightness Controls

The HUD display illumination is controlled by two sets of inputs: the base HUD background and driver selectable illumination level. The base HUD background display uses ambient lighting of the road ahead of the vehicle and an overall vehicle backlighting dimming level to determine the display illumination level. The driver then has the ability to select a desired illumination level, which is selectable through the HUD menu. When a forward collision warning event is in progress, the illumination intensity is increased to provide an increased level of severity to the visual warning.

The HUD module uses the following inputs to control the illumination brightness:

• internal combiner HUD ambient light sensor value
• HUD brightness menu

The HUD uses an internal ambient light sensor to determine the illumination level of the display. The end-point of the light guide is forward-facing. The light sensor can be cleaned with caution, but cannot be repaired or replaced separately from the HUD.

Once the HUD has established a base illumination level, the driver can then select a desired illumination level. When the driver has selected to change the intensity level, the IPC sends the HUD brightness menu message to the HUD module to open the brightness menu. The driver can then change the intensity level using the menu options.