Question about Symphonic ST420FF 20" TV

5 Answers

Symphonic WF20L6 20" TV

Television comes on and then goes off after just a minute or two.

Posted by LaVeda Cross on

  • 12 more comments 
  • saqerhussein Nov 06, 2007

    is the same problem comes and goes off less than2 seconds

  • JasonEMT Dec 02, 2007

    TV turns off after about 30 seconds.

  • Cynco Dec 12, 2007

    I am having the same problem with the tv turning off after 30 seconds. What has anyone done to get this problem resolved.

  • scran Dec 16, 2007

    I have the same problemw with the T.V. Has anyone found a solution to the problem?

  • Anonymous Dec 21, 2007

    tv goes on then and then stops working

  • Anonymous Mar 10, 2008

    TV comes on within two minutes, the sound is gone and will
    not come back on. By the way, this set was given as a
    Christmas Gift December 2007.


    Willie M. Burton

  • pjfrific Mar 11, 2008

    I am having the same problem. My TV is just over a year old when it started this. It comes on fine. After just a couple of minutes it goes off. I can turn it on again, but it stays on just a few seconds before it turns off again. It does this repeatedly. It will NOT stay on. My opinion is that something is getting hot and shutting it down. A friend suggested i get one of those compressed air cleaners to blow it out in case there is any dust in it, but I have not tried that. Hmmm...i was hoping to find a solution on-line. This is sad- obviously a faulty TV. This was a WalMart after Thanksgiving special in 2006.

  • hallslawn123 Jun 20, 2008

    tv will only stay on a few minutes then goes off.

  • talkinterry2 Sep 08, 2008

    Power problem apparently a common problem with this TV. I also bought at Walmart at the end of 2006. Has anyone actually found what the real problem is?

  • Anonymous Dec 17, 2008

    tv turn off after 30 Is this the inverter as well?

  • Anonymous Jan 05, 2009

    Warranty expired....after a year finally gave in and took it to get fixed....should cost $120.....been waiting on part about 3 weeks....supposedly coming from overseas....will post when finally resolved

  • ejtiger914 Feb 03, 2009

    TV comes on for less than a minute and goes off, I brought it to the tv repair shop & received estimate for $100 with 90 days warranty only & no gaurantee as how long the inverter might last. I am not sure I want to spend more money on it, I bought it from Walmart two years ago.

  • Roscoe007 Feb 14, 2009

    same here

  • Anonymous Mar 11, 2009

    TV comes on for 10 sec then shuts off. pls help!



5 Answers


  • Level 1:

    An expert who has achieved level 1.


    An expert whose answer got voted for 2 times.

  • Contributor
  • 1 Answer

Easy fix!!!!!!! CUT JUMPER 300 on main board _ [FACTORY DEFECT] protection jumper
If you have a warranty take TV back to store if not easy fix.

Posted on Jul 26, 2009

  • 1 more comment 
  • johnandre001 Jul 05, 2011

    That worked great thanks for the help!!

  • Pgskr8 Feb 21, 2012

    I just tried this and the TV doesn't turn off now! Thanks . I wonder, what caused it to begin with and is there a fire hazard now or any other potential issue?

  • Pgskr8 Feb 21, 2012

    Thanks Shonbrie




The problem is on the inverter's voltage regulators. Zener diodes labeled d808/9 and npn transistors (any of 11) c3199. Also on the mainboard burnt out 12v supply to inverter. Anyone brave enough can disconnect the inverter and tv won't switch-off by itself. Funai made a gaffe in the design of several LCD tvs.

Posted on Sep 10, 2008


Michael Borelli

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points


    An expert that got 10 achievements.


    An expert that got 5 achievements.

    Vice President:

    An expert whose answer got voted for 100 times.

  • Master
  • 979 Answers

Power supply faulting for internal problem..accordianman

Posted on Oct 20, 2007


  • Level 1:

    An expert who has achieved level 1.

  • Contributor
  • 1 Answer

I suggest to change transistor K3869 and Capacitor Ceramic B 1c2k 2kuv sec that is in front of transistor

Posted on Jun 24, 2008


  • Level 1:

    An expert who has achieved level 1.

  • Contributor
  • 2 Answers

Problem is on inverter board-D308 zener diode{6.2v]

Posted on Jun 21, 2008

Add Your Answer


Uploading: 0%


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



Related Questions:

1 Answer

My remote will not allow the tv to come on and stay on. screen says digital television and goes off. why?on. the tv will say ditigal television and the go off. why?

Do a factory reset to this TV. Refer its user manual for details. Just do a hard rest too. To make it hard reset, unplug the TV from AC mains wall outlet, and re-plug it after 10 minutes or so.

Jun 22, 2012 | Philips Magnavox 13MT143S 13" TV

1 Answer

TV picture goes out after 10 minutes of viewing with popping sound

It can be a couple things. Something bad on the power board. Or the vertical output circuit. How long ago did you purchase the television. Your best course of action is to have it serviced.
If you need any information or other assistance let me know.

Jun 24, 2008 | Pioneer SD-582HD5 58" Rear Projection...

2 Answers

When I press power, light blinks for about 15-20 minutes, then goes off. Press power again, on solid for 30 seconds, then goes off. Press power again, TV finally comes on.

Your television is in need of repair. Hard to tell what exactly needs to be repaired but when the power light blinks in that way then this is the TV's way to tell you it needs to be serviced.

Apr 25, 2010 | Toymax Magnavox 37MF331D 37 in. LCD TV

1 Answer


video board is shot, providing u still have sound. must replace.

Jan 27, 2009 | Dell W1700 17 in. HD-Ready LCD Television

1 Answer

Television problem

Try changing the lamp, as sometimes an old or weak lamp will cause this symptom. USE AN ORIGINAL SONY LAMP as the replacements are unreliable

Oct 11, 2008 | Sony KDF-E55A20 55 in. LCD Television

1 Answer

Thomson 27" LCD TV 27LCDB03B

cannot be presise but at worse the lcd back light is failing or the supply to it . this is a job for a service engineer

Dec 02, 2007 | Thomson LCDB 03B 27 in. Television

1 Answer

D52W17 Takes several attempts to turn on

Hello, sorry about taking so long to reply,do you still need help? If so let us know .Thank You for using FixYa and Have a Nice Day.

Oct 21, 2007 | RCA D52W19 52" Rear Projection Television

Not finding what you are looking for?
Symphonic ST420FF 20" TV Logo

Related Topics:

1,712 people viewed this question

Ask a Question

Usually answered in minutes!

Top Symphonic Televison & Video Experts

The Knight
The Knight

Level 3 Expert

76416 Answers

Cindy Wells

Level 3 Expert

6164 Answers

matt martin
matt martin

Level 3 Expert

1258 Answers

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

Answer questions

Manuals & User Guides