Circuit/System Description

The driver information center (DIC) switch is a multiplexed switch that functions as a DIC/dimmer switch. The DIC switch is also used for the head-up-display (HUD) (if equipped). The switch then functions as the HUD/DIC/Dimmer switch. The instrument panel cluster (IPC) only monitors the DIC switch inputs. The dimmer switch is monitored by the instrument panel module (IPM) and the HUD switch inputs is monitored by the HUD. Battery power is provided to the DIC switch via the instrument panel cluster (IPC). The IPC also provides the DIC switch with a low reference. The switch input to the IPC is pulled low or grounded when a switch is activated. The DIC switch is a momentary contact switch that connects a series of resistors in a resistor ladder format. The IPC monitors the DIC switch signal circuit to determine the DIC switch inputs. Each switch state - INFO UP, INFO DOWN, INFO RESET, ENGLISH/METRIC, TRIP RESET- corresponds to a certain resistance value. The IPC determines the switch pressed by the voltage drop across the resistors.

The head-up display (HUD) is a display system that optically projects vehicle information onto the windshield. The HUD has an electric tilt adjust that is controlled by the up and down switches. Operating these switches directs the motor to move the HUD image up or down on the windshield. The HUD is equipped with a page switch that scrolls through multiple messages present on the HUD. The HUD is also equipped with automatic dimming. Dimming is controlled by the HUD dimmer switch. All three switches control the HUD by grounding the HUD switch input signals. The dimmer switch uses a variable resistor to control the intensity of the HUD display.