Last week my Panasonic 42" plasma (TH42PZ77U) suffered from the 7 blinks. I found this thread (and other websites). I contacted Panasonic last week (called the number and faxed my receipt) and a repair technician (an actual Panasonic employee, not an affiliated servicer) came out today. He said the 7 blinks problem is an indicator of several different problems. Panasonic would repair it for free if it was the result of a faulty circuit board (SC board, part # TXNSCINZTU), which mine was. He said sometimes the panel itself can go bad (and give the 7 blinks), which they wouldnt fix for free. My tv is 1 year and 7 months old, and I have no extended warranty. This specific circuit board failure is thoroughly documented, so Panasonic replaced it for free. Others things he said about this issue:
-SC board failure is due to 1 specific chip on the board, but its easier to replace the whole board than soder in a new chip at someone's house
-Panasonic redesigned the board (along with a firmware upgrade) so it uses less power. the chip on the board fails because of too much heat.
-in 2008 the SC board failure was a common occurance (for his service visits), but since 2009 he hardly sees this service call anymore (mine was the first in several months). he thinks most of these have been serviced by now. he doesnt expect this problem to come back and he's never seen this problem return to a serviced tv.
-he said this problem is unique to the 42 inch model. the 50 and 65 versions of this model dont suffer from the SC board failure because of the larger panel. apparently the increased pixel density of the 42 inch screen (compared to the 50 and 65) requires greater power generation/consumption. the 50 and 65 inch versions also have 8 fans, while the 42 inch has 4 fans.
-the SC board processes power for the plasma screen itself. the processor sends the image to the board, which powers the plasma screen
thumbs up to panasonic. they called me for a service appt the day after faxing my receipt in, and the repair tech came 2 business days later. plus i didnt pay a cent.
btw I live in Los Angeles county....if it matters.