GM Service Manual Online
For 1990-2009 cars only

The head-up display (HUD) is a secondary display system that optically projects critical vehicle information off of the windshield. The head-up display consists of 3 switches:

  1. On/Off switch: The DIC can be turned on and off.
  2. Up/Down Switch: There is an electric tilt adjust inside the DIC that is controlled by the HUD up/down switch. Moving this switch directs the motor to move the HUD image up or down on the windshield.
  3. Dimmer Switch: You may manually adjust the HUD image brightness by moving the HUD dimmer switch.

During the start up of the vehicle, all segments of the head-up display illuminate for 3 seconds. The HUD displays the following features:

    • CHECK GAGES Indicator
    • High beam indicator
    • Low fuel indicator
    • Radio station or CD track number
    • Turn signal indicators
    • Values in english or metric units
    • Vehicle speed

English/Metric

The HUD indicates the speedometer in either english (mph) or metric (km/h) units. When the DIC ENG/MET button is pressed the HUD units change in accordance with the DIC units.

Radio Controls

The HUD receives a message from the radio through the E+C serial data line. The HUD will display the radio station or the CD track for approximately 3 seconds after the radio station or CD track has been changed. If the radio information does not display then there is a problem with the E+C serial data line.

Vehicle Speed

The HUD receives a discrete input from the PCM indicating vehicle speed.