"No Radio" Warning 2011 Chrysler Town & Country

My brother in law is on a road trip and his radio suddenly stopped working. The radio panel displayed “No Radio.” He stopped for gas, turned the car off and the radio was working again when he restarted the car. Is this normal or could he have a more serious electrical or computer problem? Thanks!

I haven’t seen a warning like this before.

What does the owners manual say?

Couln’t find it in the manual unfortunately : (

Aquick trip to the nearest dealer would be the best since it would be a warrenty issue.