Hello, I have Sony KF50WE610. I have already

The most common cause of No Picture - Lights Flashing, or Intermittent Picture - Picture Cuts Out in all Sony LCD TVs is bulb failure.

No troubleshooting or replacing parts should be attempted without installing a "known" good bulb. This is not a fault, the mercury in the bulb has been consumed.

Many dollars are spent on parts and service when the only problem is bulb failure.

You can replace the complete Lamp Assembly or the Bare Bulb. DIY or get a serviceman. Here is a link that shows how to change or replace the bulb or lamp in Sony KF50WE610.
Sony Lamp, Bulb, Installation Guide

Six blinks - No Horizontal (H STOP), no raster, goes to the blinking self-diagnosis function immediately. Check C515 & 516 and the jungle IC, IC206.

Not a DIY fix

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New bulb is just fine.
3 blink shows that lamp cover after replacement of bulb in TV is not fixed properly or not seated well in its position.
Put new bulb and carefully place back lamp cover in its position because lamp cover will press tinny safety switch inside that will send signal to system control of TV that lamp is installed properly.
Turn On TV and get vivid picture of Sony.
Thanks.

This model also has a paper filter for the Optic block that should be changed. No one ever said anything about it. shortens the life of the optic block if not changed.

sounds like light engine is bad call Sony and see if it is on their extended warranty list.

I had this same issue with a 46" Sony. I replaced the bulb, and it is as good as new. I hope this helps.

I had the same problem with my 4 yr old Sony KDF60WF655 rear projection set, and I was fortunate to buy a 4 year extended warranty - because it was the $1300. (not incl labor), Optic Block that was replaced to fix the problem. That part contains all new LCDs, & Lens & some electronics. I had already got a new bulb (under warranty) a few weeks earlier, that I had not yet installed so the service guy did replace that as well. (This happened 3 weeks before my warranty ended)

He told me that he replaces hundreds of Sony Optic Blocks every year and that many Sony Rear Projection sets have FACTORY extended warranties because of some known problems with the blue LCD panels.

The tech checked my Service Codes & showed me the TV had been running for 10051 hours in about 4 years - on the Original bulb! He was quite surprised because he said the bulbs usually last about 5000 - 7000 hours. He also said it's good to replace them BEFORE they go bad, because they can sometimes burn out the amplifier that powers the bulb, (which is a seperate piece that attaches to the outside of the Optic Block). My TV is like new now.

I hesitate to tell you this for fear of a bad rating from you, but it is likely the optical block is the source of your problem. Sony was covering replacement of the optical block for this unit until June of 2008, but that warranty extension has expired. I would suggest you contact Sony customer support at 800-222-SONY to see if they will allow for some type of accommodation to cover either the parts, the labor or some portion thereof. Sorry!

Yes the light with the sun around it, as you discribed it, is the light that tells you the bulb is out. Your set uses a Sony part number XL-2100U bulb abd that is available HERE http://www.partstore.com/PartSearch.aspx?PartNumber=XL-2100U&x=15&y=18 I would go for the first one, as I have found replacements for a little less cash just do not woirk the same and do not last the same. Good Luck

Check the optical block repair at sony's warranty website...
Could be the problem they have been covering it under a recall of sorts. $1250 for the optical block and they are only doing it until the end of the year so don't waste any time