Why does our 50in tv powers on then powers off right away and what do we need tobuy for part

Backlights blown, T-con board faulty or Main board fault!

I think somehow that the input is changed. locate the input button on your remote and toggle between all the input to find your lost signal

Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/tony_a41fa0b801734e2f

Did you try to use button on TV to turn on? Maybe remote battery bad?

If the problem is same with different input devices and you have ensured there are no loose contacts in power outlet, RC jack, cable and sockets, the TV needs servicing.

Check the link below to find info on how to DIY.
http://www.fixya.com/support/t5692386-problem_philips_50pf9631d_50

The power supply board is gone. You can get parts from here: TV Parts Universal TV Stands DLP Chips ShopJimmy

buffer board needs replaced need to replace both

don't open the tv because they have a problem inside your tv and after that if you want .................................................................................later.

Try this link to zenith it should take you directly to the Product support page. Click on Product Support in the menu bar then click on the owner's manuals link on the left side of the page. You'll want to select TV as the product group, then PDP TV as the product, ENGLISH for the language, and finally type in the model number.

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