crwdns2934241:0crwdne2934241:0 Chris Green

crwdns2934249:0crwdne2934249:0:

try to open it, and clean the lens and look for any  dislodged  cables, or any damage to the drive's internals, here is iFixit's drive manual:  
http://www.ifixit.com/Guide/Repair/Repairing-Jammed-Optical-Drives/772/1

crwdns2915684:0crwdne2915684:0:

open