Check your tolerance setting for the cruise control. See post below - it will read the speed limit sign and then add whatever value is set. It's also possible it misread a sign...
Maybe this is related?
https://www.mustang7g.com/forums/threads/tsbs-ssms-and-recalls-for-the-24-mustang.157809/
11. 12/19/23 - 52142 - "Intermittent No Crank/No Start Condition With Various Lost Communication DTCs Stored In Various Modules And Multiple Illuminated Warning Indicators Displayed...