Solved! Samsung N150 shutdown randomly

[aliston2021]

The switch button was not in the best shape and I am using the notebook like this for more than 5 years, trying to not physically touch the button, using shutdown/restart/standby commands but anytime I was force to use the power switch it works fine. Suddenly the notebook started to shutdown by itself and I have a hard time keeping the power on. Sometime stays on days, sometime just shuts off in 2 minutes. Sometimes it starts by itself on and off 5 seconds cycle. First I thought the power switch is gone but the switch is just a short that can be made between 2 wires to initiate the POST and this is accomplished but why does not keep the power on? I monitored CPU core and ISA temperature and maximum was 60 Celsius (when laptop was ON) average 40 Celsius. I check and clean fan and MB (no dust deposits). I tried to power on battery only or power source only and same symptoms. The most intrigue is why is starting to boot by itself when the laptop is power off state (NOT STANDBY/SLEEP)? Any help would be much appreciated, thanks!

 

[mrmike16]

From what you're saying, it's all related to the power button, which of course can turn the laptop on and off by itself if it isn't connecting properly - The laptop is detecting random signals from the power board. If you want to be sure, you can try using it without the battery and with a different charger that meets your laptop's specifications to make sure it isn't from a power supply.

 

[aliston2021]

I am wondering if it is a way to keep the power on always? I can short the switch but even the led turn on for a second the laptop does not start. Conversely if I use the damaged switch sometimes does initiate boot and stays on who knows how long.

 

[BEAUFORD_SAVAGE]

If the power switch is sticking on, especially intermittently this would account for the symptoms given. If you don't feel a normal switch action, replace the switch.
It does NOT sound like the external power supply at all. if the computer was off, and the power supply came on by itself, it would not turn on the computer You need to take care of the obvious problem before you can do any further trouble shooting.