Question about ViewSonic N3250W Television

1 Answer

I too am having a, seemingly rampant, problem with my Viewsonic N3250w. I tried unplugging the power cord to reset the power supply. This allowed the TV to run fine for over an hour. Then it started to turn itself off again. The green "power" LED remains on when it does this. It seems that others who tried to get their's fixed under warranty ran into many problems with customer service. I really want to fix this issue on my own. I've read here that the problem possibly stems from the capacitors on the power supply itself, but I am drastically under qualified to replace them myself. If anyone can help by providing a list of the necessary tools, supplies, and possibly even a schematic for reference. I'm afraid to break it, but as it was a gift I don't have the money to have it fixed. Thanks in advance.

Posted by on

  • 2 more comments 
  • craven23 Sep 11, 2010

    Thanks for the help. Fortunately this does seem fairly easy, and my brother knows how to solder. He also has a soldering gun, so we'll be doing this together. Again thanks much.

  • craven23 Sep 11, 2010

    Yes this solution was helpful. It gave me detailed instructions, and a complete list of items I would need to fix the unit myself.

  • craven23 Mar 28, 2011

    I asked this question quite some time ago, and am just now getting around to fixing it. The problem I'm having is that this expert advise turned out to be wrong. Not that it's bad advise, just that the problem is not the capacitors. When I got the unit opened to the power supply i noticed that none of the caps were busted or bulging. I'm afraid now that I don't know what course of action to take in getting this set repaired.

  • craven23 Mar 28, 2011

    On top of the new revalation about the problem not being the caps, now I fear that the power supply board that I have in my television is the replacement board for the Darfon 4H that was originally in the unit. If it's not the capacitors, and not the power supply, then what could be causing this issue?



1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points


    An expert that got 20 achievements.


    An expert that got 10 achievements.


    An expert that got 5 achievements.

  • Master
  • 1,606 Answers

Replacing caps is not hard unless you don't know how to solder. Then it becomes rather easy to cook the new caps or the board.

First you need screwdrivers etc to get inside the case and get everything apart. Bad caps used in power sections will either bulge or leak. The top will budge out/up slightly. Normally they will be flat or slightly indented. They are cheap so the usual practice is to replace all of the power section caps in one go. If the power fluctuated enough it can have damaged the rest so if you just replace the bad caps you may get it all running and have one of the 'good' ones fail a little while down the road.

So the first thing you do is mark the cap out and make a shopping list of what you need. Caps are rated in farads and volts. You can;t change the farads or micofarads for these and you can only use the same or greater volt rating never down. So if they are the same physical size then the solder pads will line up and thats the last thing to match up.

To remove them you need a soldering iron and solder wick (aka solder braid) and sometimes solder. You place fresh solder wick on the solder pad of the part, place the hot iron on it and as it heats both wick and solder the solder moves into the braid.You move the the other side and repeat. At this point it should move or be loose. Sometimes when they are stubborn you have to apply solder then desolder. This helps flow the solder out. Eventually it will come off. And repeat as required for the rest of the caps. If you do a video search for desoldering (google, bing, youtube) you should find one that shows this technique in a bit of detail. Surface mount stuff is not hard just different to do.

To solder them is quite easy. Clean the pads free of solder using more braid. The solder one pad. Place the cap on top (making sure its polarity is the right way) heat the solder, make sure the cap is in the right spot so it touches both pads and remove the heat. When the solder cools you just apply solder the the other pad and that should be it.

The soldering iron should be no more than a 15w with a grounded tip. The tip shape can either be a fine/small chisel or a needle point. Solder has to be electronic solder and fairly fine.
A pair of tweezers or forceps is handy. And you want lots of light.

As far as a schematic I can't help you with that. Not sure one is even available for this unit. I won;t say that you shouldn;t attempt this as it is a fairly simple job but if you can get some piece of junk board and practice pulling the parts off and putting them on. Then you won;t be getting up to speed on the good stuff.

Posted on Sep 10, 2010

  • Dave King
    Dave King Sep 11, 2010

    I hope you mean a soldering pencil or iron and not actually a solder gun. ;-]

    The guns put out waaaaay too much heat so they cook things real quick and they are not well grounded so they can put enough power into a board to kill static sensitive parts. A pencil or iron cab be as cheap as a $10 thing but is not something you should try to replace. Static and excess heat will damage or kill the parts so you need to keep a eye out for these.

    Oh I briefly mentioned electronic solder. The solder part is the same but I keep getting things to fix because someone thought that plumbers solder and flux would work just as well. Thats acid based and meant to solder pipes mechanically together. The acid eats away part of the pipe to give the solder a tooth to grip to. In electronics it works but the acid flux keeps on working an eventually eats away the circuit board or even parts of components or wires and so on. Basically once you use it, the part is junk. You can't get it back off so eventually it's going to have a problem.

    If you or your brother plays with some dead junk first then you will be good to go on the tv. Dollar store yard sales etc will always have a dead radio or something that you can play with and not worry.



1 Suggested Answer

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

A 6ya expert can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
The service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
Good luck!

Posted on Jan 02, 2017


Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

Why does Viewsonic N3250W TV show a grey rectangle on the screen

Try a factory reset to this set. To do this, you have to enter its service mode option. If you wish to get some details; check the site linked here. Viewing it in "Mosaic" or "Magazine" will make surf easy. Pull up older posts. Surf the site with patience. Do a search by type in the brand name of your device at its search box.
Service mode entry, adjust and exit procedure to many popular brand TVs are given. Never forget to exit the service mode, after all adjustments have been done.

May 26, 2014 | ViewSonic N3250W Television

1 Answer

ViewSonic N3250W will not turn on

Do you get a red standby light at all? If not, I'd look first for the standby transformer as being defective. There may also be a fuse right by the AC power cord. Look around inside and update this with your results. Post whether or not there is a standby. We'll need to go step by step on this one.


Jul 03, 2008 | ViewSonic N3250W Television

1 Answer

I have a viewsonic n3250w that won't turn on. where do I start?

Unplug the TV from the wall outlet. Press and hold the power button for about 10 seconds. Wait five minutes and then re-apply power.

Nov 26, 2010 | ViewSonic N3250W Television

1 Answer

Viewsonic N3250w. Power supply went out and I replaced the bad capacitors. TV worked for a week then now when I turn it on, the screen just turns on and off

Check to see if the 24vdc disappear when the screen black out, it is always there then you have problem in the backlight inverter board. Did you replace the caps in the 24vdc supply also? I replace the whole set.

Capacitors kit: he can make you a set of caps for yo

Sep 05, 2010 | ViewSonic N3250W Television

1 Answer

Hi, Q7 in the power supply

the pin at one side is the base, et the other side top is colector and bottom emiter, looking the transistor face flat down.


Apr 01, 2010 | ViewSonic N3250W Television

2 Answers

Viewsonic N3250W I replaced the power supply board but when I turn on, the screen flashes real quick and there is no picture.

it was not the power supply its the invertor board that controls the back lighting/switch on screen flashes lights go off/shine torch into screen ull see picture/get new invertor board 7 or 8 little plugs go into it

part or repairs in uk ohm supplies

Jan 08, 2010 | ViewSonic N3250W Television

1 Answer

Viewsonic N3250w no power

Look at the power supply first; look for burnt parts, bad capacitors, etc.
Please post back what you find

Dec 06, 2009 | ViewSonic N3250W Television

1 Answer

Power cord connection issue---we have tried different power cords. Issue is where it connect to set. The power will come on, but the set will shut off

This failure might not be in the power cord but the internal power supply. If your LCD is older then 15-18 months for sure it needs a power supply replacement.
Symptons of a failing power supply are:
1- Set does not powers ON.
2- Turns OFF by itself.
3- Needs to be unplug to make it powers ON again.
4- When the set is ON, it produces a humming noise through the speakers.

You can find a power supply replacement visiting this website and you should be able to replace it yourself.

Oct 17, 2009 | ViewSonic N3250W Television

1 Answer

ViewSonic N3250w

The defective power supply module will cause the following symptoms:
No Display and no Sound, Then Power indicate light changes from Green to Red.
Turns OFF by itself.
Needs to be unplug to make it work.
Works for a few minutes then turns OFF.
I repair these power supplies, if you need further assistance

Aug 22, 2009 | ViewSonic N3250W Television

Not finding what you are looking for?
Televison & Video Logo

Related Topics:

294 people viewed this question

Ask a Question

Usually answered in minutes!

Top ViewSonic Televison & Video Experts

Cindy Wells

Level 3 Expert

5382 Answers

The Knight
The Knight

Level 3 Expert

75304 Answers

Donald DCruz
Donald DCruz

Level 3 Expert

17130 Answers

Are you a ViewSonic Televison and Video Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides