The Captain gave an interview to a turkish newspaper (Millet). Maybe someone has the link and can translate it for us. I believe this would clear a few points.
As I understand it he already left the airplane and than turned around and talked to the pax to make sure no other crew will accept the airplane and fly it.
The nature of the defect is also explained. I hope someone can translate for us.
http://www.milliyet.com.tr/2006/09/27/son/sontur18.asp