# TV switches on by itself **URL:** \ **Category:** Factual Questions\ **Tags:** trump\ **Created:** [February 12, 2025, 2:27am UTC](https://boards.straightdope.com/t/tv-switches-on-by-itself/1014213 "2025-02-12T02:27:25Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Happy\_Lendervedder](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/happy_lendervedder/32/8488_2.png) [@Happy\_Lendervedder](https://boards.straightdope.com/u/Happy_Lendervedder)\ **Post date:** [February 12, 2025, 5:43pm UTC](https://boards.straightdope.com/t/tv-switches-on-by-itself/1014213/21 "2025-02-12T17:43:33Z")
I know I can set up a Roku app on my phone to use on my TV. I don’t remember from the set-up process how easy it would be to connect it to a neighbor’s Roku-powered TV. Perhaps a neighbor is using some similar app-based technology to mess around with you? Or perhaps, in the process of setting up their app, they simply connected the app to the wrong TV that was in range of their cell phone. ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [February 12, 2025, 5:46pm UTC](https://boards.straightdope.com/t/tv-switches-on-by-itself/1014213/22 "2025-02-12T17:46:40Z")
But like visible light they can bounce off reflective surfaces. It is at least possible that a neighbor’s remote is reflecting in. ---
**Author:** ![Marvin\_the\_Martian](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/marvin_the_martian/32/2898_2.png) [@Marvin\_the\_Martian](https://boards.straightdope.com/u/Marvin_the_Martian)\ **Post date:** [February 12, 2025, 5:47pm UTC](https://boards.straightdope.com/t/tv-switches-on-by-itself/1014213/23 "2025-02-12T17:47:06Z")
What brand and model of TV? Is it connected to the internet? If so, if it is a smart TV the owner might have it linked to an app and accidentally turned it on remotely? Is anything connected to it as an input? I believe some devices can turn on the TV over HDMI. ---
**Author:** ![Digital\_is\_the\_new\_Analog](https://avatars.discourse-cdn.com/v4/letter/d/a88e4f/32.png) [@Digital\_is\_the\_new\_Analog](https://boards.straightdope.com/u/Digital_is_the_new_Analog)\ **Post date:** [February 12, 2025, 9:49pm UTC](https://boards.straightdope.com/t/tv-switches-on-by-itself/1014213/24 "2025-02-12T21:49:37Z")
> [@Marvin\_the\_Martian](#): > > I believe some devices can turn on the TV over HDMI. Yes - for some devices and some HDMI ports. I use my firesticks to turn on my TVs. It even works via Alexa by voice, without a remote control involved at all. ---
**Author:** ![Noelq](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/noelq/32/16438_2.png) [@Noelq](https://boards.straightdope.com/u/Noelq)\ **Post date:** [February 13, 2025, 12:36am UTC](https://boards.straightdope.com/t/tv-switches-on-by-itself/1014213/25 "2025-02-13T00:36:29Z")
If you have a cable box from a cable provider, like Xfinity, they do a daily update on their cable boxes. I went into the settings on it, and set the updates for 4 a.m. so they don’t interrupt anything. Sometimes, after one of these updates, it sometimes turns the TV on. Perhaps you had an update at this time? ---
**Author:** ![Johanna](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johanna/32/8318_2.png) [@Johanna](https://boards.straightdope.com/u/Johanna)\ **Post date:** [February 13, 2025, 1:49am UTC](https://boards.straightdope.com/t/tv-switches-on-by-itself/1014213/26 "2025-02-13T01:49:07Z")
That sounds the closest of all proposed explanations to what could have plausibly happened here. ---
**Author:** ![needscoffee](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/needscoffee/32/1076_2.png) [@needscoffee](https://boards.straightdope.com/u/needscoffee)\ **Post date:** [February 13, 2025, 1:59am UTC](https://boards.straightdope.com/t/tv-switches-on-by-itself/1014213/27 "2025-02-13T01:59:17Z")
> [@wolfpup](#): > > Unexplained occurrences like this can usually be blamed on a cat. I can’t count how many times my cat has done this. Stepping on _any_ button on the Roku remote turns the TV on. Not that I’m suggesting my cat is visiting Johanna while I’m at work. ETA: That I know of… ---
**Author:** ![Banksiaman](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/banksiaman/32/3334_2.png) [@Banksiaman](https://boards.straightdope.com/u/Banksiaman)\ **Post date:** [February 13, 2025, 3:16am UTC](https://boards.straightdope.com/t/tv-switches-on-by-itself/1014213/28 "2025-02-13T03:16:14Z")
I had the same think happen with my TV - a Samsung and searching showed that it happens occasionally with that model, and a series of possible fixes were offered. My first suspicion was that it was my neighbour who has a similar version tv and whose set pops up when I look for devices to connect, but she denies everything and blames the supernatural. Ghosting in every sense … Yes it does flip you out the first time at 3AM. ---
**Author:** ![notfrommensa](https://avatars.discourse-cdn.com/v4/letter/n/f14d63/32.png) [@notfrommensa](https://boards.straightdope.com/u/notfrommensa)\ **Post date:** [February 13, 2025, 3:43am UTC](https://boards.straightdope.com/t/tv-switches-on-by-itself/1014213/29 "2025-02-13T03:43:26Z")
I don’t mean to be a smart -ass but If a TV is just being parked at your house and never used, why is it plugged in? ---
**Author:** ![Johanna](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johanna/32/8318_2.png) [@Johanna](https://boards.straightdope.com/u/Johanna)\ **Post date:** [February 13, 2025, 5:24am UTC](https://boards.straightdope.com/t/tv-switches-on-by-itself/1014213/30 "2025-02-13T05:24:11Z")
It’s used on occasion when its owner visits. ---
**Author:** ![JacobSwan](https://avatars.discourse-cdn.com/v4/letter/j/a6a055/32.png) [@JacobSwan](https://boards.straightdope.com/u/JacobSwan)\ **Post date:** [February 13, 2025, 11:20am UTC](https://boards.straightdope.com/t/tv-switches-on-by-itself/1014213/31 "2025-02-13T11:20:06Z")
> [@Marvin\_the\_Martian](#): > > All those Tesla charging stations? Transmitters to control all the local TV sets. In the UK, it’s the other way around. Radio 4 broadcasts secret codes that control domestic electric meters. > **[Radio teleswitch](https://en.wikipedia.org/wiki/Radio_teleswitch)** > > A radio teleswitch is a device used in the United Kingdom primarily to allow electricity suppliers to switch large numbers of electricity meters between different tariff rates, by broadcasting an embedded signal in broadcast radio signals. Radio teleswitches are also used to switch on/off consumer appliances to make use of cheaper differential tariffs such as Economy 7. > The typical use of a teleswitch is to manage the start and end times of off-peak charging periods associated with tariffs suc... ---
**Author:** ![Shoeless](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/shoeless/32/7099_2.png) [@Shoeless](https://boards.straightdope.com/u/Shoeless)\ **Post date:** [February 13, 2025, 3:52pm UTC](https://boards.straightdope.com/t/tv-switches-on-by-itself/1014213/32 "2025-02-13T15:52:59Z")
> [@needscoffee](#): > > > [@wolfpup](#): > > > > Unexplained occurrences like this can usually be blamed on a cat. > > I can’t count how many times my cat has done this. Stepping on _any_ button on the Roku remote turns the TV on. > > Not that I’m suggesting my cat is visiting Johanna while I’m at work. > > ETA: That I know of… This isn’t exactly the same thing, because in our case the TV was already on. Our TV has the cable box as the primary HDMI, and we have a DVD player and a Roku connected to other HDMI ports. If you turn on the DVD player or press a button on the Roku remote, the TV will automatically switch to that device. There have been a few times when my wife and I were watching TV, nobody is within arm’s reach of the Roku remote, and the TV will spontaneously switch to the Roku. ---
**Author:** ![Elmer\_J.Fudd](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/elmer_j.fudd/32/1211_2.png) [@Elmer\_J.Fudd](https://boards.straightdope.com/u/Elmer_J.Fudd)\ **Post date:** [February 13, 2025, 4:45pm UTC](https://boards.straightdope.com/t/tv-switches-on-by-itself/1014213/33 "2025-02-13T16:45:31Z")
As someone who worked as a CATV technician almost 40 years ago, I can attest that TVs turning themselves on is nothing new. Nobody had a conclusive answer for why except it was always sets with a remote control. ---
**Author:** ![ashtayk](https://avatars.discourse-cdn.com/v4/letter/a/e68b1a/32.png) [@ashtayk](https://boards.straightdope.com/u/ashtayk)\ **Post date:** [February 13, 2025, 4:46pm UTC](https://boards.straightdope.com/t/tv-switches-on-by-itself/1014213/34 "2025-02-13T16:46:11Z")
The phone works as a Roku remote only if they are all on the same Wi-Fi network. And it’s pretty cool - no line of sight or proximity required at all. ---
**Author:** ![gnoitall](https://avatars.discourse-cdn.com/v4/letter/g/bb73d2/32.png) [@gnoitall](https://boards.straightdope.com/u/gnoitall)\ **Post date:** [February 14, 2025, 2:46pm UTC](https://boards.straightdope.com/t/tv-switches-on-by-itself/1014213/35 "2025-02-14T14:46:22Z")
A lot of so-called smart TVs have non-infrared remotes (some wifi, some bluetooth) and therefore are immune to line-of-sight limitations. ---
**Author:** ![markn\_1](https://avatars.discourse-cdn.com/v4/letter/m/f9ae1b/32.png) [@markn\_1](https://boards.straightdope.com/u/markn_1)\ **Post date:** [February 14, 2025, 6:39pm UTC](https://boards.straightdope.com/t/tv-switches-on-by-itself/1014213/36 "2025-02-14T18:39:33Z")
There are several IR remote protocols. The one I’ve worked with the most is the so-called NEC protocol. Each button press sends a 32-bit word, with each bit encoded as either a long flash (1) or a short flash (0). Originally, the code word contained an 8-bit “address” (an ID of the device which was supposed to receive it) and an 8-bit command. The other 16 bits were a pair of 8-bit checksums, one for the address and one for the command. But as the protocol became more popular, the limit of 256 addresses became a limitation, so they expanded the address field to 16 bits and eliminated the address checksum. This greatly increased the possibility that a misread codeword could be interpreted as directed to a different device than intended. I’m not saying this accounts for the OP’s issue, since the description does not suggest that any remote was sending anything at the time, but it is a common cause of a remote accidentally controlling the wrong device. ---
**Author:** ![Atamasama](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/atamasama/32/12961_2.png) [@Atamasama](https://boards.straightdope.com/u/Atamasama)\ **Post date:** [February 14, 2025, 9:10pm UTC](https://boards.straightdope.com/t/tv-switches-on-by-itself/1014213/37 "2025-02-14T21:10:33Z")
> [@Shoeless](#): > > If you turn on the DVD player or press a button on the Roku remote, the TV will automatically switch to that device. That functionality is called Consumer Electronics Control (CEC). > **[Consumer Electronics Control](https://en.m.wikipedia.org/wiki/Consumer_Electronics_Control)** > > Consumer Electronics Control (CEC) is a feature of HDMI designed to control HDMI connected devices by using only one remote controller; so, individual CEC enabled devices can command and control each other without user intervention, for up to 15 devices.: §CEC-3.1  For example, a TV remote can also control a digital video recorder and a Blu-ray player. > It is a single-wire bidirectional serial bus that is based on the CENELEC standard AV.link protocol to perform remote control functions. CEC wiri... It allows CEC-enabled devices to control each other. If it bothers you, there should be options to disable it in your TV’s settings (or any other device). I like it because it makes it easier to switch between my Xbox and cable box. There were times when it would do it at awkward times, like I’d manually switch to one device and it would switch back on its own, but I updated my TV’s software and that behavior went away; it now behaves more predictably. ---
**Author:** ![Shoeless](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/shoeless/32/7099_2.png) [@Shoeless](https://boards.straightdope.com/u/Shoeless)\ **Post date:** [February 14, 2025, 9:16pm UTC](https://boards.straightdope.com/t/tv-switches-on-by-itself/1014213/38 "2025-02-14T21:16:10Z")
I don’t mind it, other than the fact that it switches to another device automatically but I have to _manually_ switch it back. ---
**Author:** ![Dropo](https://avatars.discourse-cdn.com/v4/letter/d/ce7236/32.png) [@Dropo](https://boards.straightdope.com/u/Dropo)\ **Post date:** [February 14, 2025, 9:22pm UTC](https://boards.straightdope.com/t/tv-switches-on-by-itself/1014213/39 "2025-02-14T21:22:49Z")
Probably not applicable, but I recall a time some years back when it was discovered that a key ring being jiggled a few feet from the TV was turning it on. Repeated experiments confirmed the cause-and-effect beyond doubt. Note that a similar sound could be produced by a wind-chime, among other means. ---
**Author:** ![Marvin\_the\_Martian](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/marvin_the_martian/32/2898_2.png) [@Marvin\_the\_Martian](https://boards.straightdope.com/u/Marvin_the_Martian)\ **Post date:** [February 15, 2025, 12:32am UTC](https://boards.straightdope.com/t/tv-switches-on-by-itself/1014213/40 "2025-02-15T00:32:03Z")
Old (mid-1950s through mid-1970s) TVs had ultrasonic remote controls - if you could afford such a high-end TV. My dad’s boss had one, but we had to walk to the TV and turn a knob. Uphill. Both ways. From [Wikipedia](https://en.wikipedia.org/wiki/Remote_control): > In 1956, [Robert Adler](https://en.wikipedia.org/wiki/Robert_Adler) developed Zenith Space Command, a wireless remote.[[15]](https://en.wikipedia.org/wiki/Remote_control#cite_note-metv.com-15)[[20]](https://en.wikipedia.org/wiki/Remote_control#cite_note-Farhi-20)[[21]](https://en.wikipedia.org/wiki/Remote_control#cite_note-Verge-21) It was mechanical and used ultrasound to change the channel and volume.[[22]](https://en.wikipedia.org/wiki/Remote_control#cite_note-22)[[21]](https://en.wikipedia.org/wiki/Remote_control#cite_note-Verge-21) When the user pushed a button on the remote control, it struck a bar and clicked, hence they were commonly called “clickers”, and the mechanics were similar to a [pluck](https://en.wikipedia.org/wiki/Plectrum).[[21]](https://en.wikipedia.org/wiki/Remote_control#cite_note-Verge-21)[[23]](https://en.wikipedia.org/wiki/Remote_control#cite_note-23) Each of the four bars emitted a different fundamental frequency with ultrasonic harmonics, and circuits in the television detected these sounds and interpreted them as channel-up, channel-down, sound-on/off, and power-on/off.[[24]](https://en.wikipedia.org/wiki/Remote_control#cite_note-24) > > Later, the rapid decrease in price of [transistors](https://en.wikipedia.org/wiki/Transistor) made possible cheaper [electronic](https://en.wikipedia.org/wiki/Electronics) remotes that contained a [piezoelectric](https://en.wikipedia.org/wiki/Piezoelectricity) crystal that was fed by an [oscillating](https://en.wikipedia.org/wiki/Oscillation) electric current at a [frequency](https://en.wikipedia.org/wiki/Frequency) near or above the upper threshold of [human hearing](https://en.wikipedia.org/wiki/Hearing_(sense)), though still audible to [dogs](https://en.wikipedia.org/wiki/Dog). The receiver contained a [microphone](https://en.wikipedia.org/wiki/Microphone) attached to a circuit that was tuned to the same frequency. Some problems with this method were that the receiver could be triggered accidentally by naturally occurring noises or deliberately by metal against glass, for example, and some people could hear the lower ultrasonic harmonics. Your jiggling key ring or wind chimes probaly had ultrasonic harmonics that the TV picked up. [Previous page](https://boards.straightdope.com/t/tv-switches-on-by-itself/1014213.md?page=1) [Next page](https://boards.straightdope.com/t/tv-switches-on-by-itself/1014213.md?page=3)