GMC Sierra Owners Manual
Portable Audio Devices
This vehicle may have an auxiliary input located on the radio faceplate and a USB port located in the center console or on the instrument panel.
External devices such as an iPod®, laptop computer, MP3 player, CD changer, or USB storage device can be connected to the auxiliary port using a 3.5 mm (1/8 in) input cable or the USB port depending on the audio system.
See “Using the Auxiliary Input Jack” and “Using the USB Port” in Auxiliary Devices on page 7‑33.