I have a Sony KV-L34SN11. 80cm.When you turn it on using the remote, the sound comes on for two seconds then turns off, no picture.

SOURCE: sony tv picture keeps flashing

You likely have bad solder connections around the tuner area. This model has a history of problems in that area or the tuner itself.

SOURCE: Sony Trinitron KV-24FS100 red light flashes 4 times

your tv had a problem.if you have a knowledge in electronics, check or replace the horizontal transistor beside the plyback. it is a black square parts with 3 pins.

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.

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