i own a volvo fl6 220 truck of 2004. it doesnt start and when it starts, it runs for just 3 seconds then it stops. it also has a message data link broken. what could be the problem and how do i fix it?
I would start with checking the ECM hot wire at the battery. It's the little wire. Sometimes the little connector crimp on the end can fracture from repeated vibration. Wiggle it and see if it breaks off. Also check for corrosion on the connection. A little up the wire should be an inline fuse. If it starts then quits the fuse is good but there might be a corrosion issue there too.
Other than that I would think it was a fuel problem if it wasn't for that message.