My cameras on my 2023 Defender 110 stopped working.
The rear camera doesn't come on when in reverse, and clicking on the camera icon on the touchscreen doesn't do anything.
Was about to call the dealer to schedule service.
Solved the problem by holding down the radio/media button for 20 seconds to reset the screen/system, and the cameras are now working again.

 

Yes. Either do the above or just recycle the car by turning off (waiting a few minutes) and back on and the cameras will return. I learned we should more and more treat the Defender as a computer or smartphone. In my experience, usually reboot is the first ask when reaching to IT assistance. Second, software update.

 

Yep, right on.

Should've mentioned that I'm on the latest software (August 3, OS 4.0.1) and went thru several car on/off cycles over a period of several days, and that didn't make any difference.

Rebooting the touchscreen system did the trick.

 

This happened to my Defender once, and it reset itself.

l also had all audio go silent (which is when l realised the indicator sound comes from the speakers, and not a relay under the dash...)

But that fixed itself as well. lt hasn't happened again.