Solved! Sony VAIO Laptop SVF15218SNW boots for few seconds, but then immediately switches off


Jul 8, 2015
I have Sony VAIO Laptop Model SVF15218SNW. The problem is that sometimes the laptop boots and functions normally and sometimes it doesn't boot at all. From the last few days, the laptop when powered up boots for 2-3 seconds and then instantly switches off with a clicking sound probably coming from the HDD as can be seen in the video 1

In the second scenario, when the laptop is powered ON after few minutes, the two green leds on the keyboard remain ON as long as the battery/AC is not removed (while the front leds doesn't power up ) and the same can be seen in Video 2

The laptop doesn't boot with nothing on the display . I have tried connecting external monitor using HDMI to test the LCD , but it is still the same problem, tested using Battery and AC separately and both , still the same. I have also tested using different RAM/HDD but still the same problem.
I am facing this problem from the past one year. Is there any solution or fix for this problem?
Try another power supply? It's likely the motherboard is the issue. It's a fairly old laptop, a replacement is probably as cost effective as buying parts to fix it. Systems of that era and newer can be found for under $200 used easily.