Have you ever had the experience of turning on your TV only to have it shut off almost immediately? Believe me, I know the feeling! After dealing with this issue on my own TV recently, I decided to take matters into my own hands and do some research. In this blog post, I’ll be sharing what I learned from the research I did, as well as the tips and tricks I used to fix the issue.
TVs shut off immediately after turning them on because they have faulty capacitors and voltage regulators. The IC chip on your main logic board might be damaged, in which case you need to replace the entire board. You should disable the HDMI-CEC feature from your TV system settings.
|1. Check for damaged components
|Unplug the TV, remove the back cover, and inspect the motherboard and power supply board for any visible damage or blown capacitors.
|2. Address bad capacitors or voltage regulators
|Replace faulty capacitors or voltage regulators if they cause voltage drops.
|3. Unplug the TV
|Unplug the TV from the power outlet for 5 minutes to allow any residual electrical currents to dissipate.
|4. Disable HDMI-CEC (e.g., AnyNet+ on Samsung TVs)
|Access the TV settings menu and disable the HDMI-CEC feature to prevent continuous on-and-off cycles.
|5. Contact a TV repair shop
|If you can’t find any defects, consider contacting a TV repair shop to identify potential issues.
Table of Contents
TV Turns On Then Shuts Off Right Away
Unexplained TV issues where a TV remains stuck in a perpetual cycle of switching on and off indicate a faulty power supply board. It’s wise to check your warranty at this point, and if it’s a recently-bought TV, contact the seller to check if it’s covered.
Otherwise, if you’re feeling up to it, you can remove the back cover to check whether there are any apparent signs of damage to the boards. You don’t need to be a technician to spot leaking capacitors, missing or charred components, etc. – you can tell which capacitor is bad by observing them closely.
A blown capacitor will have a round bulge on top instead of its normal, flat appearance.
Here’s how you can check for damaged parts:
- Unplug your TV from the wall outlet – you must cut any power to the TV to avoid potentially dangerous electrical charges from hurting you or damaging the TV.
- Place the TV face-down on a flat surface – put the TV on a soft, flat surface screen-down. Feel free to put a cloth or blanket between the surface and screen for extra screen support.
- Remove the TV’s back cover – use a screwdriver or power tool – whichever is easier – to remove all the screws holding the back cover.
- Check for damaged components – When you remove the back cover, you’ll notice two boards on the TV’s interior. The green panel is the motherboard, responsible for providing your TV with the ability to compute and execute commands like a computer.
The brown-colored board is your power supply and inverter board that powers your backlight.
A word of warning: even though the TV is without a power source, some of the large capacitors will hold an electric charge, meaning you need to discharge them.
You can do it yourself by shorting two pins on the power supply board with a screwdriver that has an insulated handle; you’ll know it worked when you notice a tiny spark where you place the screwdriver.
- Disconnect the cable leading to the TV side panel (bonus) – You can try this step if you’re sure all the components in your TV are working as intended. Disconnect the cable that connects to the buttons or touch panel of the TV because it may cause your power supply to become faulty.
Otherwise, if you spot anything strange, like charred bits, blown capacitors, or anything that looks out of the ordinary, it’s best to contact your nearest TV repair shop to see if they can replace the power supply board. Otherwise, you may need a new TV.
If you don’t spot any damage, you likely don’t need a new TV, and we can continue with some of the other troubleshooting options.
Bad Capacitors And Voltage Regulators Cause Volt Drops
When a TV switches off and on by itself, and you see a red Standby light (not every TV has one), it happens due to a drop in standby voltage.
If you have a blown or lousy capacitor, it won’t hold enough charge, and your TV won’t be able to switch on, although it tries. As such, you see it turning off and on continuously, indicating that you may need to replace the capacitors.
The voltage regulator can also cause voltage drops because if it’s not sending enough power to the capacitors, they won’t be able to power your TV.
You might go a step further and swap out the main logic board of your TV or the motherboard. It could be that the IC (integrated circuit) chip on your logic board goes bad, in which case you need to replace your logic board. The IC is a small, flat, square-shaped chip. You can tell it’s bad when you see discoloration or burn marks on the IC chip.
Unplug Your TV From The Power Outlet
Sometimes a single TV component can cause the others to malfunction. In such a case, it can help to switch off your TV and unplug it from the power outlet for five minutes to give any remaining electrical currents time to dissipate. Afterward, plug it back in to see if it works.
Disable The AnyNet+ Feature On A Samsung TV
Anynet+ is the Samsung trading name for a feature of HDMI called Consumer Electronics Control (CEC), referred to as HDMI-CEC.
It allows users to control up to twelve devices attached by HDMI with a single remote control. In other words, you can use a remote of a TV to control a Soundbar or Blu-ray player connected to the TV.
However, the AnyNet+ feature can also cause issues with Samsung TVs, sending them spiraling down a path of on-and-off motions. Disabling this feature can prevent your TV from switching off and on continuously.
To switch off this feature:
- Hit the Home button on the TV remote to access the Settings menu.
- Navigate to Settings, and choose General.
- Select External Device Manager from the middle section of the menu.
- Look for AnyNet+ (HDMI-CEC) and disable it by pressing Enter on your TV remote.
How Do You Go To Settings If My TV Doesn’t Stay On?
If you can’t access the menus because your TV doesn’t allow it, don’t panic. Here’s how you can get your TV to stay on briefly to allow you access to the menu:
- Unplug your TV from the wall outlet, including the network cable and Wifi router.
- Let your TV stand without any power sources or connected cables for ten minutes.
- After ten minutes, plug it in again and switch it on. If it had one before, you might notice it no longer has a blinking light.
- Quickly press the Home button on your TV remote control to access the Settings menu and make your way to the AnyNet+ (HDMI-CEC) option to disable it.
Have A TV Repair Shop Look For Defects
It might be a manufacturer’s fault if you can’t seem to find any defects with your TV, yet it powers off and on continuously. The chances are more likely if you recently purchased your TV.
For instance, a few years back, Samsung admitted having defected capacitors in some LCD, plasma, and DLP TVs that caused them to fail.
The likely cause of a TV shutting off after you turn it on is faulty capacitors or voltage regulators on the power supply board.
It’s also worth checking the main logic board to see if the IC (integrated circuit) chip does not have discoloration or signs of charring. Lastly, consider switching off the HDMI-CEC feature on your TV because it may cause restarting issues with your TV.
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