The sceen turns a yellowy tone and then goes back to normal

KINDLY DO DESCALING BUT IF YOU DO YOU HAVE PRESS THE POWER BOTTOM FOR 5 SECONDS AND IT WILL BLINK YELLOW OR ORENGE ONLY THEN YOU CAN DO DESCALEING THE LIGHT WILL GO BACK TO GREEN BUT ONLY AFTER DESCALING

Go to the control panel and pick personalisation, then scroll down the screen and change the settings from high contrast which is what your current screen is set to.

You can change the background and colour of the text from here,

Have you tried cleaning the screen? I smoke cigars, so I have to go around compressed-airing and wiping stuff down constantly. Screens look yellow/orange if I let it go too long.

If you remove the blue from the picture, it goes yellowy in colour. Maybe a poor connection on the blue LCD unit.
If you are planning on taking a look, be very careful as a damaged flexible cable on an LCD unit will render it an expensive repair!

flex wire connecting LCD with camcorder might be a problem it's very common.I did in mine .
Good luck

hi,

try to change the battery of your unit?

Unplug Your Tv And Hold The On/Off Switch For 30 Seconds Release Then Plug It Back In Hopefully This Will Force Factory Presets.
If Not Then Look Through The Color Menus For A Factory Reset Or Defaults.

the problem with LCD tvs are that they have back lamps that shine thru the LCD sceen. the job of the screen is to block the light of the different colors to make the picture. the problem is that the very thin screen can not block all the light. if the set has a back lamp setting turn down the back lamps and adjust the brightness control it should help a little. you my notice that the blacks and dark sceens look better when the room is fully lit and look much worse in a darken room.

http://www.primaamerica.com/support.asp

Your problem most likely is in your high voltage circuit, and the 160 volt radial lead capacitor is probably gone high ESR or changed in capacitence, this usually happens during bright sceens or sceen change.