GM Service Manual Online
For 1990-2009 cars only

Parade dimming is a separate lighting mode that is activated when the park lamps are turned on during the day. Usually when the park lamps are turned on during the day, the display's illumination and LEDs become lower and the backlighting is activated. To avoid this condition, backlighting is turned off, and the displays and LEDs are set to a high predetermined intensity when daylight conditions are detected to enhance the display's visibility during daytime.