Toshiba Satellite M65-S909 laptop will not start. My Toshiba Satellite M65-S909 laptop will not

Question

My Toshiba Satellite M65-S909 laptop will not start when I press the power button, either with the AC supply connected to it or without the AC supply connected to it and just the fully charged battery in it. Previously it used to start with the fully charged battery and without the AC supply connected to it. After that if I connected the AC supply it would light up the power light and also start charging the battery. But of late it simply won't start. Sometimes it starts powering up momentarily with just the fully charged battery in it, but after that it automatically shuts down after just a few seconds. I will appreciate any help to resolve this. The laptop is not in warranty any more.