Auto Power on Laptop motherboard

Thread Starter

Saurabh Sangwan

Joined Mar 29, 2019
Hello, I am making a carputer (Car-PC) for my car.
I had an old laptop lying around I took apart the motherboard and installed Android x86 on it
Everything works fine my main issue is, how do I make it to power on automatically when I turn the ignition key.
I don't want to have a power button to press to turn it on, is there any way to do it?


Joined Jun 2, 2008
The laptop power button must of connected somewhere, have you traced it out?

Just short it out with a relay or similar when the car ignition is switched on.


Joined Jan 23, 2018
For starters, it is not a good choice to have the computer switch on when the car first starts. The voltage needs some time to settle after the large current draw from the starter motor. Digging into the computer to get to the start button is asking for a disaster, and also, that same button is used to force a shutdown when the computer locks up. So having a relay "just short out the power button will not ever give satisfactory results.
And a question: WHY do you want the computer to switch on as soon as you start the engine? AND, what is wrong with having to start the computer with the start button?


Joined Mar 19, 2019
FWIW... The laptop should use a momentary PB, not a switch. So a delay timer with a short duration output? Give the car time to start (delay on) then a momentary ON (1-2s?). One shot 555 comes to mind.


Joined Jan 23, 2018
I have wondered about using a laptop that uses a 15 volt supply on a car system directly, and the problem that I can see already is the noise on the automotive system. The one laptop that I have that does use a 12 volt supply only runs "DrDos" and so software for it is rather hard to find these days.


Joined Mar 10, 2018
There may be a setting in bios that foces restart on AC power loss (assuming
you are using a 12 DC to 110 VAC inverter to supply laptop brick).

You have to defeat password entry if you want it to boot to desktop.

Please start the Windows 10 cmd in administrative mode, enter the command control userpasswords2
select the user for Autologin in Windows 10.

Uncheck the check-box "Users must enter an user name and password to use this computer."
and click the button Apply!

Regards, Dana.


Joined Jan 23, 2018
I use such a setting in win7 for my desktop computer, but since it is useful it has probably been removed from win10. Of course, by going to auto-login you remove a whole lot of security, but that may not matter in your application.
And I am wondering what a computer running android under win10 would be useful for in a car. is the application of the computer something that you would be willing to describe?