Park Assist off on the dic red exclamation point

[Erp939]

Recently my 2014 Buick verano has been saying Park Assist off on the dic and flashing a red exclamation point. I washed the car so it's not dirt or debris. Any ideas or do I have to take it in for service? Thanks

 

[2007LucerneCXL]

A sensor may have been unplug, gone bad or module. Unfortunately I'm not sure if there is a test you can do other than check the connectors are clean and tight.