Turns itself off immediatley after turned on

i have a mitsubishi hd 1080 tv when i turn it on it turn of with 2 sec.what is the problem

Disconnect CRT Board that plugs on that tube and turn TV on, if it stays on then tube is defective

hold the menu and input/device buttons for 5 seconds and it will blink you a 2 digit code
1-2 normal operation
2-3 i believe is short circuit protection = probably a convergence failure
here is a link to my tutorial
http://www.fixya.com/support/r5001731-convergence_diagnosing_convergence
Let me know if I can be of further assistance.

no, if blink code the problem is in the TV set--cable will not cause this type of trouble

If you have a rear projection, it is the bulb. Ypou need to replace it.

The main board/switch is worn to the point it will not work anymore after a while, I been in the business for years, These are wonderful TV's, yes there are replacement parts but a quick fix your looking for here will be unsuccessful this is the reason I am providing my advice and take a chance on the rating your going to give me. Try www.ebay.com look for people that is saling parts for these TV's.

Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/edwy_1a56970cf1ea4620

looks like voltage reg.in the power supply need replace.

check the collector drop on Q29a002. If it is less than 16 nano amps, repl ic u12 in conver circuit. stk392-570 and pico fuses f04 and f05 24v circ

try holding in the menu and input buttons together on the front panel for about 8 seconds to see if the self diagnosis feature will blink a two digt code then let me know what happens

Try pushing Input and Menu together and hold them both in for 5 seconds to see if it blinks a 2 digit code which repeats itself. Then let me know what it does and we can go from there.