GM Service Manual Online
For 1990-2009 cars only

The reconfigurable head-up display (HUD) is a secondary display system that optically projects critical vehicle information on the windshield. The head-up display is controlled by a combination switch located in the vehicle center console:

  1. Page switch: The HUD displays three standard format pages including format 1, format 2, format 3, other temporary navigation information and traction/stability system messages.
  2. Up/Down Switch: There is an electric tilt adjust indicated by up and down arrows within the center of the HUD switch. Moving this switch directs the motor to move the HUD image up or down on the windshield.
  3. Power/Dimmer Switch: When the switch is in the "O" position, it is indicating that the HUD is in the OFF position. Once it is turned into the next position the HUD is powered on and now assumes the dim control of the display.

During start up of the vehicle, all segments of the head-up display illuminate for 3 seconds. The HUD display then displays the last known format before being powered down. The formats include the following:

Format 1

    • Speed
    • Turn Signals
    • High Beam
    • Park
    • Tap Up/ Tap Down/ Upshift
    • Outside air temperature
    • Compass
    • Values in English or metric units (as controlled by the DIC)
    • Temporary Warning messages
    • Radio (temporary)
    • CD player (temporary)
    • Remote multiple CD player (temporary)
    • Cassette (temporary)
    • RNDL (temporary)

Format 2

    • Speed,
    • Turn Signals
    • High Beam
    • Park
    • Tap Up/ Tap Down/ Upshift
    • Values in English or metric units (as controlled by the DIC)
    • Warning messages (temporary)
    • Radio (temporary)
    • CD player (temporary)
    • Remote multiple CD player (temporary)
    • Cassette (temporary)
    • RNDL (temporary)

Format 3 (Stealth Mode)

    • Speed
    • Turn Signals
    • High Beam
    • Values in English or metric units (as controlled by the DIC)
    • Warning messages (temporary)
    • Radio (temporary)
    • CD player (temporary)
    • Remote multiple CD player (temporary)
    • Cassette (temporary)

The stealth mode is only available at night and the HUD display will have the same content as Format 1.

Telltales

The following is a list of telltales displayed in the HUD and the source from which the HUD receives serial data messages

   • 

Compass Heading (DIC)

   • 

English/ Metric Mode (DIC)

   • 

Gear Range Selection (DIC)

   • 

High Beam (BCM)

   • 

Outside Air Temperature (DIC)

   • 

Radio/ CD/ Cassette Display (Radio)

   • 

Speedometer (PCM)

   • 

Tap Up/ Tap Down Transmission (DIC)

   • 

Turn Signals/ Hazard lamps (BCM)

Warning Messages

The HUD will temporarily display certain warning messages as it receives a serial data messages from the responsible source. The following are messages displayed by the HUD:

   • 

Check Trip Computer (DIC)

   • 

Cruise Speed Set XXX (PCM)

   • 

Ice Warning (DIC)

   • 

Stability Control Active (BCM)

   • 

Traction Control Active (ABS)

   • 

Traction Control Off (ABS)

   • 

Turn by Turn Navigation (OnStar)

   • 

Upshift (PCM)