Apparently this is a known issue with that model TV. You can try the following steps to resolve the issue...
Do a Power Reset.
1. Turn off the TV.
2. Unplug the power cord of the TV from the electrical outlet.
3. Let the TV remain without power for 60 seconds.
4. Plug the power cord back into the electrical outlet.
5. Turn on the TV.
If the issue is still unresolved, connect a different video source (ex. cable box, DVD player, Blu-ray player or gaming console) to the TV. If the vertical black or colored band still appears on a different video source, that may be an indication that the TV is for service and yiou would need to contact the nearest Sony authorized service center in your area.