Mitsubishi ws-65809

that's cause the circuit board needs replacing. A shorted or defective part will trigger the protect circuit.

Hold down the Menu and Input keys until it gives you a flashing two-digit code. That should direct your servicer in right direction.

If you're comfortable going into the set (unplugged of course), and know how to use a meter, check pico fuses F5A04 and F5A05 on the Power board (center one). If either of those are tripped, you have a convergence issue. You would either need the solder checked on the chips, or the chips replaced.

Thanks for your response however, the t.v. turns off seconds after I try to turn it on. I am unable to hold down the menu button etc.

You can still run the codes on the set. It will give you these after the set shuts down. I would recommend calling for service. Giving them the code will give your servicer a head-start. You also would want to have your signal board checked for fluid leaks from the CRT.