GMC Yukon 2007 Owner's Manual page 344

Power for auxiliary devices is not supplied by the
radio system.
To use the auxiliary inputs of the RSE system,
connect an external auxiliary device to the
color-coded A/V jacks and turn both the auxiliary
device and the video screen power on. If the
video screen is in the DVD player mode, pressing
the AUX (auxiliary) button on the remote control
switches the video screen from the DVD
player mode to the auxiliary device. The radio can
listen to the audio of the connected auxiliary
device by sourcing to auxiliary. See Radio with CD
and DVD (MP3) on page 307 for more information.
344
How to Change the RSE Video Screen
Settings
The screen display mode (normal, full, and zoom),
screen brightness, and setup menu language
can be changed from the on screen setup menu.
To change any feature, do the following:
1. Press the display menu button on the remote
control.
2. Use the remote control menu navigation
arrows and the enter button to use the
setup menu.
3. Press the display menu button again to
remove the setup menu from the screen.