Question about Toshiba CF20F40 TV

2 Answers

No raster no sound no picture only brightness

Toshiba tv i have for 5 years, the problem was tv on full screen brightness ,no sound ,no picture. but could change tv channel,see look like very dull picture, i try replace back same # flyback & memory ic that two way didnot done problem. please heip me & give me a good idea to fix up this problem .thanks

Posted by on

  • Anonymous May 27, 2008

    tv worked fine power went out now tv wont turn on .the power light comes on but thats it.no sound either.

×

Ad

2 Answers

  • Level 1:

    An expert who has achieved level 1.

    Problem Solver:

    An expert who has answered 5 questions.

  • Contributor
  • 5 Answers

Just buy a new tv,

Posted on Dec 10, 2009

Ad
  • Level 1:

    An expert who has achieved level 1.

  • Contributor
  • 1 Answer

My tv wont turn on

Posted on May 27, 2008

Ad

1 Suggested Answer

6ya6ya
  • 2 Answers

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

Hi,
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%

my-video-file.mp4

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

×

Loading...
Loading...

Related Questions:

1 Answer

No picture, no menu, black screen, no raster, sound ok


From your detailed description, it sounds that the main chroma processor IC has damaged. Raster means nothing, but the lighted screen that appears, when a TV is switched ON. For some brands, there will be a blue screen; when there is no signal input, and some others will have a bright white screen with some snow.
I advice you to contact any service technician, to get this TV repaired. 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 and press "Enter".
http://electronicshelponline.blogspot.com/

Jul 07, 2014 | Televison & Video

1 Answer

No picture but has sound


First make sure that the brightness and contrast are turned up.If the screen is lit up (that is you have a raster) then the problem would be in the video circuits.If the screen is not lit then you have a problem in the deflection circuits.A good possibility,with no raster,would be the Horizontal output amplifier.If you are not familiar with circuitry you would need a tv tech.to do the repair.

Sep 14, 2013 | Toshiba 32AF43 32" TV

1 Answer

Toshiba 24" led tv mo. 24ps1e VGA is ok raster snow is ok ,after connection of cable only chroma picture seen,no Y signal.


Try to reset it to the factory settings and Them remove the power cable for atleast 5 minutes but Will be better to power OFF for 12 hours

Jul 18, 2013 | Televison & Video

1 Answer

Toshiba CZ32V61 no picture


1) you have problem with the Raster
2) the main causes are a) raster b) picture c) sound d) synch
3) since this are not video, the problem is raster. your must
test the voltage from section horizontal out +125vdc+vertical output +80v+all other circuit +12vdc
4) test the power supply for defective. see the diagram attached

7_13_2012_10_30_34_am.png

Jul 12, 2012 | Toshiba CZ32V61 32" TV

1 Answer

Picture freezes, sound continues for 5-10 seconds. tv shuts off and comes back on after 5-10 seconds. problems reoccurs with increasing frequency.


In these cases you might be able to see a picture by shining a bright light right next to the screen front. Do not put the light there for very long or you will end up with a permanent bright spot burt onto the screen. I have discovered that applying light pressure with a 3/8" thick rubber or plastic shim corrects a panel inverter/driver board/card solder problem with many flat panel TVs. (Removing the TV back is required, try light pressure against the inverter board while wearing rubber gloves and tv is then powered on.)

Jun 14, 2010 | Toshiba 32AV500U 32 in. LCD HDTV

1 Answer

IM A TV TECH. I HAVE A SONY LCD KP-60XBR800 I HAVE NO RASTER. POWER OK, MENU OK BUT NO RASTER ON TUNER, TUNER VOLTS OK,CAN YOU HELP ME PLEASE. THANKS my email sergioaguirre0182@hotmail.com


check the high voltage with the screen control turned up high where there is no raster. suspect problem within the video circuit where there is no high voltage or defective picture tube.some time when the screen is black and the screen control advanced,you can see if the tv has video or vertical or horizontal problems on the screen.service the high voltage circuit if there is no raster or high voltage is seen.no raster can be caused by the no heater or filament in the CRT.---- a defective picture tube can cause many problems, such as, poor brightness ,missing colors,intermittent picture,poor focus,a single-colored raster,arching in the gun assembly,retrace lines in the picture,negative picture,chassis shutdown,noheater or filament lit and no raster to name a few.an open filament or heater can cause no picture or no raster symptom.a defective CRT can have an extremely bright screen.loose particles of the cathode element can lodge between the grids and cause an intermittent black and white picture. simply tap the ends of the CRT gun assembly and notice if the picture begins to flash off and on.---- with a leaky picture tube after turn on the raster dims and get extremely bright.a dim picture with no green in the raster can result from a bad green assembly. a heater-to-cathode short can cause a raster to change colour or a result in no raster at all.replace the picture tube if there is severe arching in the neck of CRT. excessive brightness with retrace lines and a vertical collapse to a thin line can be caused by a bad coil on the neck board of the picture tube.rejuvenate the picture tube when there is very bright green screen. check for the resistance change on the resistors of the CRT neck board for an excessively bright picture with retrace lines.excessive dust inside the CRT spark gaps within the picture tube socket can cause the very bright raster and the chassis shutdown.a defective video amp,luminance buffer,or reference transistor can cause a bright picture with retrace lines. -------- for getting any required parts to replace you can get it from www.radioshack.com or from www.partstore.com or from www.shopjimmy.com --------- thanks.please do rate the solution.thank you for using fixya.keep updated.

Sep 06, 2009 | Televison & Video

1 Answer

Picture to wide


This trouble symptom picture wide or"blooming", the picture becomes dim even with the brightness control full on,and there is an abnormal enlargement of picture or raster.Usually,the enlargement is uniform,but there may be some defocusing.In some circuits,the brightness control operatesin reverse(rotating the control for an increase in brightness produces a decrease) after reaching a critical point on the control. If the picture wide is not accompanied by insufficient width(a symptom of horizontal output failure) the probable cause is a high volatge circuit ony,particularly the HV rectifier and HV winding.Any circuit problem that reduces but does not completely eliminate the high-voltage output to the picture tube second anode can cause overscan. The most likely defects are leaking high-voltage capacitors,defective high voltge tube rectifiers,leaking high voltage leads,defects in high voltage circuit protective resistance,and shorted turns in high voltage winding of the flyback transformer.

Hope this may help you;

DON'T FORGET TO RATE:

Regards,

Sep 06, 2008 | Toshiba 32AF45 32" TV

1 Answer

Sanyo TV Model# DS32224


This is usualy because there is either a high voltage regulation fault, or a main power supply regulation fault.

There are many things that can cause this. When the high voltage goes too far down, the raster will enlarge. High voltage regulation can be caused by faulty components in the feedback sensing, or in the high voltage multiplier, or in the flyback windings itself.

A quick way to sort of know if the high voltage is regulating is to wind the brightness and contrast from one extreme to another and observe the raster size. If the raster is changing size with the brightness on the screen, the regulation is not working well. In some of the low cost sets there will be about a 2 to 5% raster size shift in this case. The high end sets will have a near 0% shift in the raster size. A size change of about 2% is acceptable for most sets. If the CRT is weak, this test will not work well, because a weak CRT will not properly load.

If the main power supply is operating slightly over voltage, the raster size will increase. Usualy, the brightness will be a little on the high side when the supply is too high. Voltage regulation faults can be from warn components in the voltage regulator area, or in the feedback control.

This should be looked after by an experienced TV service tech. This type of fault can be involved.

Jerry G.


Nov 09, 2007 | Sanyo DS32224 TV

1 Answer

Tv showing blue screen with flyback lines sound ok


Flyback lines? Is the picture all white with no brightness control with faint horizontal faint lines? If this is what you are saying, the screen voltage could be bad, and if thats the case, the picture tube or the flyback itself could be bad. You could also have a bad connection on the crt socket

Dec 27, 2006 | Philips Magnavox 20MT133S 20" TV

1 Answer

Toshiba 27A51 problems


reduce raster no picture no sound and the power stays on.

Oct 27, 2006 | Toshiba 27A51 27" TV

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

Related Topics:

255 people viewed this question

Ask a Question

Usually answered in minutes!

Top Toshiba Televison & Video Experts

The Knight
The Knight

Level 3 Expert

75304 Answers

Donald DCruz
Donald DCruz

Level 3 Expert

17130 Answers

Jaime Hernandez

Level 3 Expert

2336 Answers

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

Answer questions

Manuals & User Guides

Loading...