I used to have a guide back in the CarSpace days here but moved that information over to the Stuck CD discussion in the forum. A few people have added comments in there.
CD changers always sounded harder to fix with one of the "tricks" than removing a stuck CD from a player.
Sounds like about all that's left, short of having the player removed and disassembled, is to try one of the fuse tricks at that link (I guess "F31" is a fuse eh? Maybe there's another in back of the changer or the player).