TV Sony Bravia Model KDS-60A3000. Why does the picture go black and the sound stays on after the TV has been turned on for 2-3 minutes? Then after another minute or 2 the picture comes on again then goes off after the same amount of time? Note, when this happens the on/off light flashes while the picture is black. your problem?

SOURCE: I have a sony bravia 60'' projection tv

The STANDBY light will flash if the television detects an issue within the television. Some of these issues can be resolved simply by following the steps below to reset the television.
If the issue is still unresolved after following all of the troubleshooting steps, service may be required . Please note the number of times the STANDBY light flashes and relay that information to the service center.

1. Turn off the television. Unplug the television power cord from the electrical outlet.
   
2. Let the television remain without power for 60 seconds.
3. Plug the power cord back into the electrical outlet. NOTE: If the television is plugged into a power strip or surge protector, remove it from the power strip or surge protector and plug it directly into the wall outlet. If the issue is resolved, the problem is with the power strip or surge protector and not the television.
   
4. Turn on the television.

SOURCE: Sony KF-60WE610 Screen and Sound On/Off

All symptoms in your TV shows that you need to replace its Lamp as it has been consumed its life hours and TV requires new lamp. Lamp can be obtained from Sony Website. Price is $200, Hope this info will help you to enjoy your Sony TV in coming days.

SOURCE: TV Picture Goes Black

I had the same exact problem.
I removed the bulb and cleaned it. There is a small screen at the top of the bulb and it was covered with dust. Once it was cleaned I replaced the bulb and it solved the problem.
Thanks to those who posted the solutions

SOURCE: Sony KDS-R50XBR1 50 in. HDTV picture cycles on and off

Hi,
It is clear symptoms of weak lamp in TV, replace lamp to correct that problem.
Lamp replacement is easy and written in user manual of TV.
Please buy Sony original lamp for TV safety.
Thanks.

SOURCE: Sony Wega kdf-50E2000 Keeps turning off and on

Before you replace the lamp I recommend trying to clean/dust the lamp component and lamp plug in area. I had the same problem and was able to resolve it by simply blowing the dust off the lamp components and fan. Use a can of high pressure air to get into the cracks and crevices.