Cadillac CTS 2005 Owner's Manual page 121

Trunk Open
When this message appears on the display, it means
that the trunk lid of your vehicle was not closed
completely. You should make sure that the trunk lid is
closed completely.
This symbol appears with
the Trunk Open message.
Turn Signal On
If you drive your vehicle for more than about 1 mile
(1.6 km) with a turn signal on, this message will appear
as a reminder to turn off the turn signal. A multiple
chime will sound when this message is displayed.
This symbol appears with
the Turn Signal On
message.
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