Unit powers up, then shuts down

Check the picture below to find the G board on your TV.

You need to count the number of blinks between the pause. Most common is 9 blinks. Also- after you press POWER, do you hear a "click" or not? If no click and 9 blinks, you probably have a "zero cross failure" and have two options:

(1) Replace the "G" board (part # A1054157A) or have it repaired (they repair it on eBay for about $40. You ship them the bad board and they either repair and return or ship you a different repaired board) A new board costs about $80- without having to send them your board.

(2) Repair the board yourself- by replacing the two diodes on the "G" Board - (D6301 which is on top- by the small transformer) and (D116 which is an SMT component on the bottom of the board- it takes VERY steady hands and a good solder iron). The parts should cost less than $25 and are available on eBay by searching for "sony a1054157a".
.

Location of "G" Board on a Sony Rear Projection TV (KDP-51WS655)
Location of "G" Board on a Sony Rear Projection TV (KDP-51WS655)

Component D6301 location (Sony KDP-51WS55)

Component D6116 location (Sony KDP-51WS55)

check the power switch for dry joints and resolder all joints if it still doesnt work check power board for dry joints as this is a common problem let me know how u go

unplug it immediately. never tolerate a sizzle (frying noise) or a popping noise. do NOT replug. fire hazard.
contact serviceman for repairs. Sears Home Service can handle this for you.

most likely bulb is going bad and internals are dusty helping overheat the already used bulb.

Sony Part Number: 2-023-094-01 I WENT TO A WEB SIGHT CALLED WWW.PARTSTORE.COM U MAY WANT TO GO THERE AND MAKE SURE ITS WHAT YOUR LOOKING FOR IT SAID A MIRROR (51)

A 9 flash code is defined as a zero cross failure, basically a power supply fault. It is usually caused by the failure of one or two diodes on the G board D6301 or D6116. D6116 is 871908197 and D6301 is 650056721. If you can get them and are handy with a soldering iron, you can probably replace them. Be sure the set is unplugged and use care when installing them, as high voltages exist in the set even after it is unplugged. If this answer is to your liking, please be sure to rate it. Thanks! Also, a good confirmation of this is to turn the set on using the following error code display method. With the original remote, press the following buttons:
DISPLAY
5
VOL -
POWER
The set will usually turn on this way if the diodes have failed

how many times does the light blink?

IC1509 8-759-593-33 IC LA78045 35.98
Q1505 8-729-423-33 TRANSISTOR 2SC3311A-QRSTA
Replacement part
8-729-119-79 TRANSISTOR 2SC2785-FEK-HFE 1.02

these ic locations are different than yours but same part number.
is there a 2sc3311 near by LA78045?

The cn6001 part number is 1-580-843-11
The Diode part number is 8-719-843-11 (both diodes are the same)