Blue screen and Shuts down?

This problem was very much noticed on

Sony KP51hw40 television.


Many of these sets had problems with bad picture Tubes--they use a red, green and blue CRT. Most commonly the blue gives troubles--The tubes are now only available on a rebuild basis--usually not worth doing as the cost is very high.

You may have a bad blue picture tube but there is a way to deal with this first----the set has a black plastic block with six controls---three are Focus(red,green,blue) the other 3 controls are Screen controls(red, green, blue)

Someone has to remove the entire piece on the front of the set below the screen(usually a plastic part) most of the time it is secured with 3 screws on either side of the set in the back; once you remove the screws the entire piece should pull out(pull from right to left(it will not fall off or come out easy--it is held in with several large plastic pegs) With it removed there is an inspection plate with 4 screws-----the screen/focus block is behind it.

You need to look very closely at the block to identify the focus versus screen controls----one row left to right will be marked Focus and the other row left to right will be marked screen------YOU need to locate the Blue Screen control(they are black like the block) With the set on(be careful) go to a video input with nothing connected---if you see a blue screen as well as the input number turn the BLUE SCREEN CONTROL SLOWLY TO THE LEFT UNTIL THE BLUE is gone.

If this cures the problem you may only be buying yourself some time----if the blue picture tube is bad sooner or later this trouble may return----I have seen sets where this was adjusted and the set worked for a year or more with no repeat of the trouble----replacing the blue tube would likely cost you 400 -500 dollars including parts and labor.






The above mentioned details will help to understand this problem better on your television.

Mitsubishi PIP module BYPASS ?

Read the procedure as follows for PIP module bypas
The details as as follows :---
This applies to most Direct view and some projection sets made in the 1990's.
While it is possible to repair in some cases this problem it is quicker and cheaper just to bypass the module--you will no longer have the PIP function.
Here are the bypass instructions:
1.) With the set unplugged remove the back cover and locate the PIP board to the left side of the set--one wire (usually green) is soldered to the metal shield. Unsolder the lead and set it aside.
2.) The board is plugged in and you will have to release the two tabs at the bottom to pull it out.
3.) Locate the pins on the large plug (should be 12 pin) on the bottom of the board.
4.) You need to CUT the copper foil traces with an Exacto knife on pins 5, 7, 9. and 11 near the plug so they are no longer connected to the plug.
5.) You install (on the bottom of the board) a 4.7 mfd filter cap with the + on pin 7 and the - or negative on pin 9.
6.) You install (on the bottom of the board) a 4.7 mfd filter cap with the + on pin 5 and the - (negative) on pin 11.
7.) Reinstall the PIP board and make sure the caps do not touch anything near that board; solder the ground wire back to the shield.
The reason the board fails is because the surface mounted caps dry out and or leak onto the circuit board---there are a lot of them.


I have seen shops replace some of the caps and get it to work but sooner or later more go bad so usually it is better just to bypass the board and not have the PIP feature anymore.


The above mentioned details will help you out.