Cadillac 2004 Seville - Manual (Page 208)

Once you have loaded the CDs in the magazine, slide
open the door of the CD changer. Push the magazine
into the changer in the direction of the arrow marked on
top of the magazine. Close the door by sliding it all the way to the right.
When the door is closed, the changer will begin
checking for CDs in the magazine. This will continue for
up to one and a half minutes, depending on the
number of CDs loaded.
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