Vizio VT420M LCD TV - Answered Questions & Fixed issues

I'd go with a power board for starters, are the other voltages ok on the power board or are they all low

Hi, it seems a main board issue but for better assistance you can contact Vizio technical support using the information shown bellow: Email: [email protected] Tel: (877) 698-4946 Fax: (949) 585-9563 Hours of operation: Monday - Friday: 6 am to 9 pm Saturday - Sunday: 8 am to 4 pm Please have your VIZIO model number, serial number, and date of purchase available before you call.

Hi, it seems you have a faulty mainboard, but the better and more secure option to avoid spending money unnecessary it's to contact directly to Vizio technical support: Email: [email protected] Tel: (877) 698-4946 Fax: (949) 585-9563 Hours of operation: Monday - Friday: 6 am to 9 pm Saturday - Sunday: 8 am to 4 pm Please have your VIZIO model number, serial number, and date of purchase available before you call.

Fault at its main digital board. Short circuited component/s at it. Contact any service technician; or the authorized service center. If you wish to get some details; check the site linked here. Pull up older posts. http://electronicshelponline.blogspot.com/ In most cases, the main board might have to be replaced. If so, a software [firmware] update too might be necessary.

Sounds like main board fault. Short circuited component/s at it. Contact any service technician; or the authorized service center. If you wish to get some details; check the site linked here. Surf the site with patience. Pull up older posts. http://electronicshelponline.blogspot.com/ . In most cases, the main board might have to be replaced. If so, a software [firmware] update too might be necessary.

I would suspect the main board as well

Check your manual and see whether these are supported.

Send your email address to me by Fixya comment, and get a copy of the service manual by return mail.

Usually T-Con board with those symptoms.

Hi. Maybe a fuse got burned, you should take it to a service center.

The backligts lamps rarely go out, but the backlights inverter boards that drive the lamps do go out often, you may need better tech that has real experience troubleshooting LCD TV.
Power supply, main board can also cause no lights on the screen. I would get second opinion.
Please read my guide to understand how LCD TV works.

Basic LCD monitor and TV troubleshooting guide: http://www.fixya.com/support/r5093881-lcd_flat_panel_tv_troubleshooting_guide http://www.fixya.com/support/r6150077-basic_lcd_monitors_troubleshooting http://www.fixya.com/support/r7406380-tv_training_manuals Failed TV and Monitors pictures: http://s807.photobucket.com/albums/yy352/budm Learn about bad caps: http://en.wikipedia.org/wiki/Capacitor_plague Parts: www.shopjimmy.com Parts: http://interliquidparts.com/ Capacitors kit: http://lcdalternatives.auctivacommerce.com/Default.aspx he can make you a set of caps. Or www.digikey.com, just make sure to use caps with low ESR, 105c, high ripple current and long life rating such as PANASONIC FM or FC series. Please post back what you find.

Hi,

This kind of symptoms indicated of malfunction on the power supply board and/or the LCD controller board.

Out of regulation on the power supply board will produce that kind of symptoms feeding the LCD controller board. This was caused by faulty electrolytic capacitor in the output of the power supply board. Sometimes it has a physical indication of fault like bulged/dome at the top but not all, capacitor checker is needed to determine its condition.

If the output voltage has already been confirmed good, the connectors from the LCD controller board must be pull-out, inspect, and then re-insert and ensure that they are properly seat-in. If the symptoms still persist, this board must be replaced with new one to back the unit in normal operation again.

If you don't have necessary tools and test instrument and can't troubleshoot the unit yourself, I would advice you to look for a professional to isolate the problem.

Also, check if your unit is still under warranty/extended warranty period, avail it because the manufacturer will fix it for free. Opening the back cover will void the warranty.

Hope I helped you.

Have a nice day!

Thanks for using Fixya.

The main board of this Vizio is known to fail after some use.

Its number is CBPF9D1KZ4 and as you will see it is hard to find, unless you want to pay $250 or so, which doesn't make any sense, at least to me.

Another common failure in those is the T-CON board, but from the sound of it the problem you have is in the main board.

Here's what I'd do if I were you: post a local ad on Craigslist, sell it to the highest bidder and use the money towards puchasing a new TV.

Not sure it's what you want to hear, but it's what I tell some customers and thus losing business that I couldn't have had anyway because it's insanely expensive and prone to more failures anyway.

If it helps you please vote for me - it helps me in turn :-)

www.coppelltvrepair.com

As of April 7, 2011 Vizparts.com has new shipment of main board #CBPF9D1KZ4 for $250.00 with a $50 core value, and 14 business days to return if not the problem. Also check Ebay search

The flickering is most likely due to a faulty fluorescent backlight. Once the bulb heats up the flickering usually goes away. Some bulbs are easier to replace than others so I would contact your local TV repair shop.

Hi,
I just now called vizio and read your request word-for-word to their technical support person.
They have been known to fix these sets out of warranty. Although the girl said that she wasn't authorized to make that decision.
She told me to have you call this number 877-698-4946 Tomorrow when their level 3 technicians were available. She says that when you call the 1st tier tech support person will then send you one to these senior techs who can make the decision to cover it under warranty. My personal opinion is that they will take care of you. They say the "squeaky wheel gets the grease" I would go ahead and squeak. There is a link I've provided below to help.
I hope the helps,
Mark
http://www.vizio.com/index.php/support/#warrantydetails

Now the tv u turn on u have a flashes of a picture only few sec. and died have sound left only?Yes,than the 2 long boards call the LCD inverter boards are the causes and the problems.These 2 long LCD inverter boards help the LCD screen panel to have a backlight to produced a picture.Tries websites like Shopjimmy.com,Ebay.com to buy those 2 refurbishes long LCD inverter board for the replacement.

You my have a bad capacitor. I had a similar problem with my 42 in Phillips. I did some research and found that a lot of electronic devices made only a few years ago were having all sorts of problems because of capacitors. They fail after 2-4 years due to a lack of preservative. If its still under warranty no big deal. If you are not, you might look into getting a new Power Supply Board.

If you are willing to open your TV up and take a look at the capacitors on the PSB(the board that the power cord comes into) you may find your problem. Blown capacitors look bulged or leak. sometimes they show no sign of a problem but if there are any visible signs you know for sure.

They are replaceable but it takes a few soldering skills.

where is channel set up

Sounds like a main board issue. Beware, some Vizio main boards can be hard to find and expensive !!!