This from sony''s web site
http://www.css.ap.sony.com/
Why does the TV standby indicator flashes when switching on the TV?
Applicable Models
KV-AR21 Series, KV-AR14 Series, KV-HW21 Series, KV-AR342 Series, KV-AR292 Series, KV-AR252 Series, KV-AR34M80B, KV-AR34X80B, KV-AR29M80B, KV-AR29X80B, KV-AR25M80B, KV-BT21 Series, KV-BM14 Series, KV-BM21 Series, KV-XR Series
Article ID: 5564 (modified: 3/20/2006 10:03:00 PM)
Problem/Question:
The TV standby indicator flashes when switching on the TV
Solution/Answer:
When switching on the TV, the standby indicator flashes green for a few seconds before the picture rises. This does not indicate a malfunction.
The picture rise time (about 14 seconds) is needed for TV to perform some internal processing. However the sound can be heard (in about 3 seconds) before the picture appears on the screen.
If the TV microcomputer detects some technical fault in the circuitry, the LED will continue to blink with no picture appearing on the screen. If this happens, please switch off the set and arrange for Sony service to check on the set.