Get the build sheet for your coach from Thor. The build sheet will give you the model number of the camera switch that was installed. Download the installation instructions and use those to check for voltage across the correct wires when the turn signals are activated. If voltage is present replace the switch. If voltage is not present troubleshoot back to the vehicles turn signal circuit.
The other option is to listen to other folks, follow their suggestions and pray it fixes the problem.
Then again, you can take my approach, buy a new switch and talk the dealer into throwing in a new RV free of charge. Caution: those switches can be expensive. I found that out when replacing a 7 Pin fuse on the Challenger (got a free Accolade) and prior to that the tires on the SunSeeker (got a free Challenger).
As a note, on our Challenger they had to replace the AV614 radio twice before we got one that would not arbitrarily shut down on its own. But like others have said, if one camera displays the radio is not bad and the issue is between the vehicle's turn signal circuitry or the camera switch.
US Army (Ret)
2020 Entegra Accolade 37TS
2019 Jeep Grand Cherokee Trailhawk (Toad)
FMCA - F432054