This model kp-51HW40 uses two of the STK-392-560 CONVERGENCE IC CHIPS.
Usually
just both chips need to be replaced and the set adjusted with the
Sony
remote---You can buy a pair of the chips on Ebay for less than 14
dollars plus
shipping.
If you can do this
repair you can save the set and a lot of
money as most
shops will charge 300 or more for this kind of repair.
I can give you general instructions if you think you can do it---there are places on the
internet that sell
kits for this--usually very pricey and many of the included parts are not usually needed.
IF CONVERGENCE WILL NOT ADJUST: BOTH CHIPS NEED TO BE REPLACED.
IF YOU HAVE QUESTIONS OR NEED HELP, LET ME KNOW, I am here to help people.
If this information helped you, rate this solution as I do this here for free.
SD TECH