Question about Sony Grand WEGA KDF-55XS955 55" Rear Projection HDTV

1 Answer

Possible begining of optical block problem

My Sony has been a good TV for the most part. I have had to replace the bulb and the Thermal fuse due to the dusty corner it is in. Now I am beginning to get a faint purple smudge on the bottom that looks familiar to a tube tv with a magnet next to the screen. i notice it sometimes get better and worse. I noticed while playing a Kids disney DVD game that it appeared to e getting screen burn from the word that were on it. Is there any way to fix this or prevent it.

Posted by on

  • 1 more comment 
  • Freddy Torres Mar 11, 2009

    Is there a way to prevent it .

  • tom_gillespi Mar 17, 2009

    How did you know when you had to replace the thermal fuse? I'm having issues with my TV also. I have a 6 blink code which means there is no DD 6Volts output on G1 Board (power supply board)

    Can this be becasue of a bad Thermal fuse?

  • tom_gillespi May 11, 2010

    What was the indicator you needed to replace the thermal fuse?


1 Answer

  • 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.


    An expert whose answer got voted for 500 times.

  • Sony Master
  • 1,779 Answers

Yes my friend, it is your Light Engine. Quite expensive to replace.

Posted on Mar 10, 2009

  • Jim Krause Mar 11, 2009

    As far as us Technicians go, our opinion is that DLP sets had no business in the home consumer market place. They were designed after the multimedia projectors that companies use for meeting purposes. The optics portion of the DLP unit is made up of polarize-rs (best described as a tinted mirror) these become very hot from the lamp and in time start to dis-color in which starts to cause the type of problem your experiencing. The only way to slow this down is keep the sets playing time to a minimum. I'm sorry about your situation. If you plan on buying another set in the near future let it be an LCD 1080P. If you need advice on the brands e-mail me at "


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.

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%


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



Related Questions:

1 Answer

After replacimg bulb tv still flashing red

we bought our Sony Wega in 2006 - we changed the bulb twice both times they exploded; we threw this tv out one month ago - sorry but its literally GARBAGE! within the first year the optical block went, then the replacement under my extended warranty that optical block was defective-within a month all the purple hues started showing up again - warranty over - never will I purchase a 4,000 tv nor any sony products ever again! the only good product I ever liked of sony was the Walkman!

Jun 28, 2014 | Sony Grand WEGA KDF-42WE655 42" Rear...

1 Answer


The Optical does not on its own have a "Thermal block" some Sony sets do have a thermal fuse connected to the Lamp---on most (What is model number?) that will result in shutdown and a 3 blink error code on the front of the TV.

Mar 19, 2012 | Sony Televison & Video

1 Answer


To reach the thermal fuse you will have to remove the optical block assembly. Remove the back of the tv, about 12 screws. Removed the large support plate, and the small support bar on the left. Remove the buttom screw on the large fan on the lower right. Remove the connections to the bass speaker and the fan connections. Slighty lift on the large board assembly on the left and it comes right out after the small support is removed. There are two hidden screws holding in the optical block. You will need a long phillips screwdriver to loosens these two screws. They will loosen, but not come out. This will allow you to remove the optical block enough to to get to the front section of the TV. You should see the bulb attached to the optical block. If you look close, where the bulb was resting, there is a plastic plate with two screws, and a wire running through it. That is the Thermal Fuse. Remove the two screws and you will be able to remove the Fuse. Install the new fuse and reassemble. I recommend you remove the cooling fan on mounted above the bulb and clean it. This fan gets very dirty. Good luck.

Jun 14, 2011 | Sony Grand WEGA KDF-55XS955 55" Rear...

1 Answer

I replaced the bulb and the power light turns green then goes red blinking

Try replacing the thermal sensor. Under the optical block.

Jan 18, 2011 | Sony KDF-E50A10 LCD TV

1 Answer

Sony Grand Wega 60WF655 TV blue tint/spots

sounds like your optical block lenses has melted due to heat.
( common problem) here is the light engine/optical block number


Mar 18, 2009 | Sony Grand WEGA KDF-42WE655 42" Rear...

1 Answer

Please help-question about sony optical blocks

Talk to Sony about the blue blob issue, they may still replace the optical block for free.

If not, fix the blinking light TV.

Blink Codes
3X - Lamp cover not installed correctly, usually after lamp change, or cover detect switch is bad.
4X - Check fans (one or more failed to pass RPM test during power on diagnostics)
5X - Lamp ballast (power supply)
6X - Usually the thermal fuse - usually from inadequate air flow (fans dusty)

All other codes usually require a trained technician to diagnose and repair.

Oct 29, 2008 | Sony Grand WEGA KDF-60XS955 60" Rear...

2 Answers

Replacing Thermal Fuse in Sony Grand Wega KDF-E55A20

The PROPER way to replace the thermal fuse is to remove the optical block first. There are at least two recessed screws holding the block in place. BE VERY CAREFUL removing the block as it is very easy to tear/rip wires when doing so. I cannot emphasize enough NOT TO JUST THROW THE NEW THERMAL FUSE INSIDE THE CABINET!!!! The thermal fuse is a safety device mounted near the lamp to prevent overheating. Those that choose to just let the fuse "sit out in the open air" are risking greater failures and the possibility of fire.

May 27, 2008 | Sony Grand WEGA KDF55E2000 55" Projection...

1 Answer

Sony kdf 50we655

heat and dust are two major problems with this type of set.These set can get very dusty inside the optics and cause this type of discoloration .Heat can cause deteriation on optics and or optics cabinet parts .It is possible to clean the optics block for dust issues only but unless you know what your doing and know what areas not to touch inside optics block .Otherwise the block would have to be replaced..

Nov 12, 2007 | Sony Grand WEGA KDF-50WE655 50" Rear...

Not finding what you are looking for?
Sony Grand WEGA KDF-55XS955 55" Rear Projection HDTV Logo

234 people viewed this question

Ask a Question

Usually answered in minutes!

Top Sony Televison & Video Experts


Level 3 Expert

100140 Answers

The Knight
The Knight

Level 3 Expert

70943 Answers

Donald DCruz
Donald DCruz

Level 3 Expert

17129 Answers

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

Answer questions

Manuals & User Guides