I have the 2nd generation Fire TV device which replaced a Fire Stick.
The Fire Stick would power on my TV and switch to the correct HDMI input when I pressed a button on the Fire Stick remote. The new device doesn't seem to do this.
How can I enable this feature please?
There is no direct setting within the Fire TV to control your television power. However, some televisions have an auto-detect HDMI setting that will allow a device, such as the Fire TV, to turn on the television when there is activity at the HDMI port. There is no common name for this setting, it may be referred to as HDMI-CEC, CEC, E-link, EasyLink, etc. Your television manufacturer's website should have more information on if this setting is available and what it is called.
Some customers have also used third party remotes to accomplish this same task, and hopefully they will weigh in with more advice!