Hello, Is there any danger traveling on the KKH from Islamabad to Northern Pakistan?
Are there any checkpoints which can result in problems? Is the whole highway under govt control? thx....

A few months ago there was sectarian violence around Chilas, which could be potentially dangerous if tensions flare up again and you're in the wrong place at the wrong time. The area around Besham is generally not an area where foreigners are the most welcome.
All in all the KKH is safe. Many travelers take this route every year. The condition of the road and traffic is by fare the greatest concern.
Nothing bad has happened with a foreign travelers on KKH so far,this means its asafe highway for foreigners.
If you are going through the public transport then opting for NATCO, the government owned transport company, will make it safer and less inconvenient.
If you are with an organized trip then the operator should know how to take you safely.
In both the cases there are no major security threats. There were some sad incidents last year but they had the sectarian 'Shia-Sunni' touch, so avoid talking about religious issues on the way.
The Kohistan area is considered relatively dangerous, where buses travel in a convoy with police escort, but not all the times.
and yes you put it right; chances of an accident are far high!
KKH is safe. There is no direct risk for the foreigner.
Are there any checkpoints which can result in problems? Is the whole highway under govt control?
If you have a valid visa then there is no problem. These all security check point are for the security of people.
It all about you!
It is safe to travel through Karakorum high way. The Police check points along the road are for the safety of people and to maintain law and order situation in the area.
recently some traveler,s travel from Islamabad toward gilgit and they told that everything is safe.
NP