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BACKLIGHT IS PULSING

WHEN THE TV IS ON FOR ABOUT 30 MINUTES THE BACKLIGHTS STARTING PULSING

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My TV is not as bright as it should be, the sound is just fine. What is the problem?


Either the backlight or the brightness have been adjusted down or the backlight bulb is starting to fail (doesn't apply to LED backlights)

Jan 26, 2017 | Televison & Video

1 Answer

Vizio intermittent backlight


You have to check the power supply of the tv. Normally led TVs power suppy is integrated with the led driver. If the led driver is faulty then this type of problems can occur.
If you wish to get some more details then check the following link.
http://electro-medical.blogspot.com/

Jul 21, 2016 | Vizio E601I-A3 60-inch Class Razor LED...

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LED TV - replaced power board but still no backlight? LED backlights do not seem to work.


yes the led backlight for whatever reason is not functioning and that is the root cause of your problem. Unfortunately to find a replacement led backlight is tough as the backlight is normally fixed with the lcd panel and has to match the voltage and all that stuff with motherboard. and if that doesn't match you might short the tv itself. this case is as good as getting a replacement lcd panel.

Feb 17, 2016 | Seiki SE50FY10 50-Inch 1080p 60Hz LED HDTV...

1 Answer

Over the last couple of days my tv has no picture intermittingly


If the TV is older than 3-5 years or do, it is probably an LCD model with a fluorescent backlight. These backlights have issues with the inverter boards and/or the tubes failing over time. This is why newer flat-panels have gone to LED backlighting. Without the backlight, the picture is actually on the screen, but you aren't able to view it because there is no light to illuminate it. These CAN be repaired, but the cost of new TVs makes it almost most cost-effective to upgrade to an LED TV.

Sep 06, 2014 | Samsung Televison & Video

1 Answer

Where do I purchase a backlight for my vizio 42in tv? And the price?


you cant the backlights are an integral part of the LCD panel. The backlight inverters Boards) can be replaced but the actual backlights are inside the LCD panel assembly.

Oct 29, 2011 | Vizio P2 42 in. HD-Ready Plasma Television

2 Answers

How can you tell if the bulb on a vizio gallevia 47 inch lcd hdtv needs to be replaced? could there be a less expensive reason why the power comes on but the screen does not come on and how would test for...


LCD TV's don't have a bulb. They have backlights (usually compact fluorescent tubes) and a panel of LCD pixels. So you can have one of three things fail: the video board, the inverter that drives the backlights or the backlights themselves. If the problem happened suddenly the inverter is more likely to have failed. As the backlights fail, the screen slowly dims or the image will become pink/red. Look closely at the screen, if you see a dim image then the backlight has probably failed (block the room light but try looking with a flashlight from a few inches away from the screen). If you see nothing, the inverter or the video board are more likely suspect.

For an out-of-warranty TV, open up the back of the TV and remove the shielding. Look for any scorch marks or bulging or damaged capacitors. (Sometimes other parts will fail on this part but these can be spotted easily. Capacitors look like cylinders on a tripod.) The scorch mark and smoke may indicate a resistor or zener diode that had been used as a fuse and is now gone.

If you borrow (or have a) high-end multimeter (able to measure high frequencies - 50 kHz) or an oscilloscope, hold the multimeter probes a fraction of an inch apart about an inch above the inverter board and power up the TV. If you see a 1 or an actual value, you have a good inverter. If you see a reading near 0, the board is bad or the multimeter can't resolve the frequency.

In either case, you can buy a replacement inverter for $50-150 and just do a simple swap. Disconnect all of the wires (connections are similar to molex and ribbon cables in a computer) and remove board (a few screws usually). Connect the cables to the new inverter. (If you google backlight inverter replacement, you'll find videos and text descriptions.) Note the part number on the board, including the Rev number, and order the exact one (shopjimmy.com or lcdparts.net are good starting points). Universal inverters do exist but can result in reversed controls (up to lower the brightness). Replacing individual parts on the board is cheaper but more prone to not tracking down all of the bad parts.

If the inverter is good, then it's probably backlights themselves (several in most TVs). These are sandwiched on the perimeter of the TV (usually under some tape that holds the lamp, reflector and other parts together. You need to order by length and width and get ones for your TV size. Separate the panel from the bezel. Remove the tape, and separate the reflector (make a note of how things are put together) then you have to Dremel (or use another rotary tool) to remove the plastic to get the backlight out. (They are often molded into the frame.) Then put in the new backlight and reassemble everything. (http://www.lcdparts.net/howto/default.aspx) but for an overview: http://www.inventgeek.com/Projects/BacklightFix/overview.aspx Then push the new backlights into place, reconnect the wires and close up the sandwich of tape and other parts around the screen. Then replace it in the bezel.

With a good spare backlight, you can test an inverter for condition (plug together and turn on the tv while the box is open). Similarly a good inverter can test the backlight.

I hope this helps.

Cindy Wells

Sep 22, 2010 | Vizio GV47LF Television

1 Answer

My display is black. If I hold a flashlight up to the screen, I can barely see the picture. What is wrong? What can I do to fix it?


The backlights have probably failed. You should also check the inverter that drives the backlights (it's like a ballast for a fluorescent light).

The backlights are sandwiched on the perimeter of the TV (usually under some tape that holds the lamp, reflector and other parts together. You need to order by length and width and get ones for your TV size. Most TVs have more than one backlight. Open up the tv, remove the shielding and carefully separate the screen from the bezel. Remove the tape, and separate the reflector (make a note of how things are put together) then you have to Dremel (or use another rotary tool) to remove the plastic to get the backlight out. (They are often molded into the frame.) Then put in the new backlight and reassemble everything. (http://www.lcdparts.net/howto/default.aspx) but for an overview: http://www.inventgeek.com/Projects/BacklightFix/overview.aspx Then push the new backlights into place, reconnect the wires and close up the sandwich of tape and other parts around the screen. Then replace it in the bezel.

To check the inverter, open up the tv and remove the shielding. Then use a high-end multimeter (able to measure high frequencies - 50 kHz) or an oscilloscope, hold the multimeter probes a fraction of an inch apart about an inch above the board and power up the TV. If you see a 1 or an actual value, you have a good inverter. If you see a reading near 0, the board is bad or the multimeter can't resolve the frequency. While you are looking at the board, check for any scorch marks or bulging or damaged capacitors. (Sometimes other parts will fail on this part but these can be spotted easily. Capacitors look like cylinders on a tripod.)

In either case, you can buy a replacement inverter for $50-150 and just do a simple swap. Disconnect all of the wires (connections are similar to molex and ribbon cables in a computer) and remove board (a few screws usually). Connect the cables to the new inverter. (If you google backlight inverter replacement, you'll find videos and text descriptions.) Note the part number on the board, including the Rev number, and order the exact one (shopjimmy.com or lcdparts.net are good starting points). Universal inverters do exist but can result in reversed controls (up to lower the brightness). Replacing individual parts on the board is cheaper but more prone to not tracking down all of the bad parts.

With a good spare backlight, you can test an inverter for condition (plug together and turn on the tv while the box is open). Similarly a good inverter can test the backlight.

I hope this helps.

Cindy Wells

Sep 15, 2010 | Westinghouse SK-26H520S 26 in. LCD HDTV

1 Answer

When I turn on my Akai, I sometimes get a clear picture and then it fades out I still see what I'm watching but its faded out, the people on the tv look florescent


This could be the backlight failing (most often the images will tend to go pink). If the TV is out of warranty, you can replace the backlight(s) yourself. lcdparts.net has many backlights but you need to match the length and width to the original. Next you need to open up the back of the TV and carefully remove the old backlight(s). The backlights are on the perimeter of the TV (laptop screens started with one but most TVs have several to maintain an even lighting of the image).) The removal takes some work and paying attention to how the original is put together. The backlights are often molded into the frame of the TV and a Dremel or other rotary tool is needed to get the backlight out. Google backlight replacement for videos, pictures and descriptions of the process.

I hope this helps.

Cindy Wells

Jul 08, 2010 | Akai LCT3701AD 37 in. LCD Television

1 Answer

My tv shows a picture for about 10 minutes then no more picture but sound remains. what could the problem be? thanks


One of two problems:

1) You have a problem with your power board/inverter. This is most likely the result of busted or bad capacitors on the power board. If you know what you are doing, you can try opening up the TV and taking out the power board and replacing any bad capacitors using a soldering iron. If not, take it to someone you trust.

OR

2) Your LCD backlight panel is going bad. The backlight is the light that shines through the LCD to show your picture. This can be fixed by 1 of 3 ways, you replace the whole LCD panel and backlight (expensive), you can get your hands on a broken LCD of the same size with a working backlight and swap out the backlights (takes time and knowhow), or you can actually repair the backlights themselves (much harder and somewhat dangerous).

The fact that it happens consistently or after 10min implies that it might be an issue of the backlights overheating until they shut off or power board overheating to the point where it can no longer provide enough power for the backlight. Try keeping a fan on at the side or back of your TV and see if it makes a difference. It may or may not make a difference, regardless of the issue.

Aug 15, 2009 | Hitachi Televison & Video

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