Apple TV has stopped turning actual tv on or off

[scsjason]

I have a latest model apple TV and when I first got it, a year or so ago, and connected it to the tv it just seemed to figure out how to control the volume and turn the tv on off when itself was turned on or off. I regularly take this device to another location and when connected to another tv the behaviour is the same. Returning the my own home and connecting to the normal tv all is well.

The other day I took it elsewhere in my own house, connected it to a wired network (wifi not good in that part of the house) and connected it to a projector. It was fine.

However, I have now returned it to its normal tv and it has stopped turning the tv on/off, forgotten how to control the tv volume and no longer connects to the wifi! Obviously fixing the wifi is easy, but why has its behaviour changed?

As to controlling the tv, it now refuses to figure it out on its own. I have done a full reset and started again, but it still refuses to recognise that it can control the tv. I have 'trained' it with the tv's remote for volume and set up a "named remote" for it to mimic, but it refuses to turn the tv on/off and I can no longer even set that option to auto as it says it is "not possible in this configuration"

What the hell has happened ?

 

[Slartibart]

Can you kindly check which version of tvOS is running?

 

[scsjason]

Can you kindly check which version of tvOS is running?

15.6

 

[Banglazed]

I had a moment of glitch with the remote as well. My issue had appeared unexpectedly like yours where the volume control stopped working with my sound bar connected to the TV via optical. I deleted the saved control device and learn a new device again but did not work. I got it working by trying the steps in the link below.

If your Siri Remote or Apple TV Remote isn't working - Apple Support

If your remote isn't working as expected, learn what to do.

support.apple.com

 

[-Gonzo-]

Sounds like due to removing from your tv it’s messed up the HDMI CEC handshake.
I’d start by unplugging and reconnecting.
I followed this when I had issues.

HDMI-CEC is really finicky about the order that devices are plugged in, as this affects the handshake that makes the system work. Where HDMI-CEC isn’t working properly, you need to turn everything off at the plug and remove all HDMI cables from your TV.

Next, turn your TV on first. Then, if you have any external sound devices (soundbar or AV amp), you need to plug these into an HDMI port on your TV first, and then power them on. Next, plug in a set-top box, such as Sky Q, via HDMI and power it on. Finally, follow up with media players and Blu-ray players.

This should make HDMI-CEC work properly, so turning on Sky Q, for example, will turn on the TV and set it to the right channel. However, don’t be surprised if turning off a set-top box leaves the TV on, as this is often the case.

 

[w5jck]

I agree with @gonzo. I think this isn't necessarily an ATV issue but a TV issue. The unplugging and replugging eventually confused the TV and it can no longer complete the handshake with the ATV. I know that when my Sony Bravia is turned on it occasionally gets a momentary bit of confusion over which device is connected to each HDMI port, but it figures it out within a few seconds. This occurs even without unplugging and replugging items.

 

[scsjason]

Thanks for the suggestions. Several power cycles of the tv/appleTV made no difference, but taking the hdmi from a different device and plugging it into the appleTV and suddenly it was working again. Swap the cables back to how they were before and all still working.