I installed a 12v to 19v converter & wired up the plug to fit the laptop but I get the message "The Smart AC Adapter power output is too low for this computer".

I did the same thing on my last boat, it was an older lappy though, and it worked fine.

I then bought, off ebay, a cig lighter adapter specifically for my HP lappy & I still get the same message.

There is a centre pin in the plug, apart from the +ve & -ve, that senses the power requirements of the laptop & this won't let it charge.

Does anyone know how to make this work so I can run my 19V lappy from my 12V system??????