No need for a promotional code. Just do a hotel search from www.radisson.com. In the "Search Special Rates" drop down menu select AAA/CAA Rate. When the list of available hotels shows up you will have one of two options (depending on the hotel).

You may see a button that says "Apply Discount." By pressing that button, it will apply the AAA/CAA discount to all elgible rates.

If no discount button comes up, the screen will simply show you what the AAA/CAA rate is for your selected dates.

Keep in mind. AAA/CAA discounts are not available at all hotels and not available on all dates.