Roku not working on Samsung smart TV, saying it needs to be powered on
Hi, so I recently got a Roku express and a Samsung smart TV and for the first week or so it worked perfectly but now when I try to go to the roku it says “check device power” and “signal error” and to click to button on screen to turn it on but it doesn’t work. I’ve tried everything I’ve found online and ever factory reset my TV but nothing works. The little light blinks for a little then turns off so I don’t know what to do.
This is not the universal solution one would think. It depends on the TV and its USB port(s) - some will work fine. Plugging into house power does eliminate this as a variable.
There are a couple of potential issues with powering your Roku via a TV's USB port, depending on your TV:
The ports on many televisions only supply 0.5 amp or less, which is not enough to power a Roku reliably. It may appear to start up okay, but when it runs into something that requires more power than the TV's USB port can provide, something's got to give. Frequently this results in shutting down the stream you are viewing and exiting back to the Roku home screen.
If this is a new problem, possibly an update to either the Roku operating software or to some channel app software is using a little more power than in the past, triggering this problem with a USB port that was just barely providing enough power before.
The USB port(s) on your TV may be marked with the amps they provide. (I have a Samsung with two ports, one marked 0.5 amps and the other marked 1.0 amp.) For most Roku models 1 amp is probably the minimum acceptable (although some recent models do come with 1.5 amp adapters) -- higher is okay as the Roku will only draw what it needs.
Powering via a USB power adapter plugged into house power can eliminate this as a potential issue.
The USB ports on some TVs remain powered when the TV is turned off, but many TVs USB ports power down when the TV is off. When connected to a powered down port, the Roku must boot up each time the TV is turned on. For many TVs this just means you have to wait for the Roku to finish its start up and arrive at the Roku home screen before you can use it. But in some cases a TV with a fast start option may start up and check its HDMI ports before the Roku is ready to respond, resulting in a "No Signal" (or something similar depending on the TV) notice from the TV until something causes the TV to check the port again.
Unplugging/replugging the Roku's power should trigger a new HDMI check by the TV and restore access. On many TVs, switching to a different input and back may force a new HDMI port check as well. Also, on some sets it may be a configurable option whether the USB port powers down with the TV, or the TV may have multiple ports, one of which remains powered.
So on some TVs, powering your Roku via house power may solve a problem or two. It is certainly something to try as a troubleshooting step when faced with the symptoms described above, but to say you MUST do this in all cases is an overstatement.
Roku Community Streaming Expert I am not a Roku employee, only a user like you. Please, no support questions via private message -- post them publicly to the Community where others may benefit as well. If this post solves your problem please help others find this answer by clicking "Accept as Solution.".
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Re: Roku not working on Samsung smart TV, saying it needs to be powered on
Hello, I know this post is "dated" but, have/had the same issue. Recently bought a 4k Stick and Samsung smart TV. Properly connected the stick to the TV and plugged stick directly to wall outlet. I've search the internet and tried everything. Nothing worked. In fact, it got worse. Contacted Roku and they mailed me a replacement but that did not work either. My new Samsung TV recognizes the Roku but, the Roku gives me "signal not found" message. When the TV offers me the option to power on the Roku, it does not power on. The only way to make this work is to physically power the stick manually.
Finally, made the decision to abandon Roku all together. Many hours invested in trying to make this work but, came up short. After years of using the Roku platform, bitter sweet to say good-bye to Roku. 😞