Working but no picture or sound

Rudy, are you connecting to the TV with HDMI, or RCA cords? HDMI carries both picture and sound thru 1 cord, whereas RCA splits it to YELLOW RED and WHITE. The HDMI connection is automatically detected when connected to your TV. It will say"HDMI is detected, do you want to use these settings?" RCA is not automatic, and is prone for the video(YELLOW) cord to develope a bad connection. I wouls duggest first replacing the cord. They are inexpencive, and the fastest way to check your issue. I am going to include a link to a youtube video that will guide you through the steps on how to reset your video settings on your system.
How To Reset PS3 Video Settings PS3

Check the video out settings of PS3.

try adjusting the settings make sure you are not set to hd when you might be sd tv, also if you are using a hdmi cord try a different cord bad cords can cause bad picture.

hope this helps if not please post more details rattling sounds, crackle or popping sounds etc..
more than likely it will be in settings

What is probably happening, is your PS3 is set for the wrong type of output. If you are using an HDMI cord, try switching to the AV cables that came with your PS3, and set your TV at the appropriate input to correspond with the AV hookups, and see if the picture works then.
If you are using the AV cables, it may have been set to HDMI accidentally. You need to use an HDMI cord, and hook the PS3 up to an HDMI compatible TV or monitor, and select the HDMI input. Once you get the picture working, go to Settings>Display Settings and set the display you wish to use.

Interesting problem. I recommend trying a reset of the video card. It's pretty easy, Sony has the instructions here.

Except for the scrambling and freezing, it sounds like an issue I had recently with my own system. Give this a try and please leave a comment on weather it worked or not.

be sure all cords are plugged in correctly and that the tv itself works if nothing helps and its not any of the cords you may need to get it looked at.

If it works on other televisions, than the video cord must be good. Is the television on the right input channel? If it is, the video input may be bad. You should test the video input with a dvd player or vcr. You can always plug ps3 into a vcr, and vcr up to televison.

you need an optical lead for the sound and hdmi for the picture

make shur the cords arnt lose

When you start your PS3, press the power button and hold it for 5 seconds. It will beep and reset the machine to the default settings. What is happening is it is thinking you are still using the other cable. Reset to default and it will recognize the new cable. Hope that helps.