The last model of the Cadillac Deville was produced for the 2005 model-year. For 2006, the Deville was replaced by the Cadillac DTS, a very similar vehicle. If you need to set the clock on your Cadillac Deville, you can do so with the keys in or out of the ignition. You’ll need to set the clock for seasonal time changes or if the battery is replaced or disconnected.
Locate the “HR” and “MN” buttons on the right side of the radio’s interface. “HR” is on top; “MN” is on the bottom.
Push either the “HR” or “MN” button once to display the time on the radio screen.