My Philips flat screen 47pfl7422d/37 has no sound or picture. what should I do?

Hi the link below has a FREE user manual download in it but the question and answer should help you........CHEERS..

QUESTION
I have lost my personal settings. Why is this?
Your personal settings were probably reset after you had switched off your TV because it is still in the LOCATION SHOP mode. In this mode, all settings are fixed and will automatically apply each time the set is turned on.
ANSWER
To store your personal settings, make sure your set is in LOCATION HOME mode:
1. Press the MENU/BROWSE key on the remote control.
2. Select TV menu and press the button
3. Select Installation and press the button
4. Select Preferences and press the button
5. Select Location and press the button
6. Select Home and press the OK button
7. Press the MENU/BROWSE key to browse through the menu

Philips flat HDTV 47PFL7422D 47 LCD integrated digital with Perfect Pixel...

A problem like this could be a lot of things. What you are describing sounds like over heating or component failure in one of the boards.

If you have tried using different input devices, looked for loose contacts
in power outlet, RC Jack, cable and connectors, the TV might need service.

Looks like the TV has developed dry solder/dry/shorting capacitors. To make sure, first of all try the same input device on some other TV. If it works there, you can be sure that your TV is having problems. Then I would advise you to stop using it to stop aggravating the defects. It is better to show it to a qualified service technician.

I had same problem, replaced both inverter boards, works perfect, found them on eBay 70 bucks

I was told to replace the master and slave inverters as the capaciters were popped, still didnt fix the problem, have you had any luck???

u need to know the sequence of the red blinks it is a code that will tell you what board or boards need replacing it is a fairly common problem but will definately cost $$$$

you can try an software update
you find it on the philipssite and have to put it on a usbstick then load it into the television

Your mainboard needs to be replaced.

You can get one on ebay and replace it or get someone who can do that for you.

if you still have guarantee, it is covered, if not you will need to buy it.