Have Sony Trinitron Wega KV-30HS420 with blinking standby/timer light that is flashing 7 times between pauses. Sound plays when powered on, but abruptly turns off after about 2 seconds. Picture never appears.

SOURCE: Sony Trinitron Wega kv-36fs120 wont turn on, standby/timer LED flashes 9 times.

try checking the soldered joints on the main circut board that attach the larger metal components...I re-soldered aprox 40 connections and now the tv works great!

SOURCE: Sony wega trinitron KV-34HS420

did a quick google got this:

http://www.techlore.com/article/15444/Understanding-Sony-Television-Blinking-Codes/?page=6

blinking is the self diagnosis working.

SOURCE: Sony Trinitron 2002 model # KV-32HS500

Mine never blinked 7 times but 6, 5, 4 times Yes

SOURCE: Sony FD Trinitron WEGA KV-32HS500...red standby light blinks 6 ti

I have over 10 years experience in electronic tech support.

I know this isn't what you want to hear, but the problem you've described can't be fixed with troubleshooting. Your TV will have to be repaired. There is a part that has developed a defect and needs to be replaced. If you're still in warranty, the TV will be repaired at no charge to you. The warranty would likely be at least one year from the date of purchase from the manufacturer. If you purchased an extended service plan they will repair the TV at no charge as well.

If the TV is no longer in warranty, it will likely cost a minimum of $150 parts and labor. This is assuming that you only need one circuit board or small part. If the problem is more than one of the circuit boards, the price of repair could go much higher.

I hope I've provided you useful assistance and that this information allows you to make an informed decision as to how to proceed from here. Please be sure to vote on my response. I hope I've earned a good rating from you today.

Please let me know if I can be of further assistance.

SOURCE: Sony FD Trinitron WEGA KV-32FS120 timer flashing 9 times

WARNING- VOLTAGES STORED INSIDE YOUR TV CAN KILL YOU EVEN AFTER ITS BEEN UNPLUGGED FOR DAYS..your problem is in the zero cross detect circuit . youu should take it to a repair facility. -Or replace diode D647 . Or on remote in this order press "display -5- vol down - pwr ." and then you could watch it right now ..kinda

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