Pontiac 2002 Bonneville Owner's Manual page 214

You must first load the magazine with discs before you
can play a compact disc. Each of the 12 trays holds one
disc. Slide the button on the top of the magazine and
pull gently on one of the trays. Load the trays from top
to bottom, placing a disc on the tray label side up. If you
load a disc label side down, the disc will not play and an
error will occur. Gently push the tray back into the
magazine slot until it locks into place. Repeat this
procedure for loading up to 12 discs in the magazine.
3-40
Once you have loaded the discs in the magazine, slide
open the door of the compact disc (CD) changer. Push
the magazine into the changer in the direction of the
arrow marked on top of the magazine.