I took the dvd changer out of the van, removed the black front plate and the silver top plate with the Model No sticker on it. I then removed the screws for the plate underneath (ie. there is one screw on the side you'll need to remove) the top plate and was able to lift up the dvd unit enough to take tweezers and lift out the dvd that was laying on top causing the error. I put it back together, put it back in and haven't had a problem since. I think it is caused by an electrical surge or stoppage while the dvd player is operating/changing. Mine occurred when/after I replaced the battery.
the hardest part was removing wiring harness from back of unit when I pulled it out. There was very little room to pull the dvd player forward to be able to unlock the wiring harnesses with your hand.