Circuit/System Description

The head-up display (HUD) is a secondary display system capable of reflecting important vehicle information on the windshield. The vehicle information is displayed using virtual imaging and is reflected off the windshield in front of the driver. Battery positive voltage is the power source to the HUD system. The HUD system can only be enabled when the ignition is active and in RUN position. The HUD receives vehicle information to be displayed via the serial data circuit. The HUD system also receives vehicle speed information via discreet vehicle speed signal circuit. The HUD interfaces with the HUD switch via discreet circuits and the HUD switch inputs to the HUD is low. The image down and image up switch are used to vertically adjust the HUD image on the windshield to accommodate various vehicle operator heights. The HUD dimming up switch initiates a smooth increase in the HUD display intensity until the switch is released or maximum intensity is achieved. The HUD does not have a separate Off switch. The HUD is turned off using the HUD dimming down switch. The HUD dimming down switch initiates a smooth decrease in the HUD intensity until the switch is released or the HUD is turned OFF.