I can't believe this is the first time I've been able to get back to the forum since I startd this thread.
Answering kgerry's questions out of order:
2) I had to remove the unit from the vehicle and completely disassemble it. Before removing the unit I tried every noninvasive thing I could think of: I turned the unit off/on in every combination of modes I could think of. I pulled the fuse several times, waiting one minute, 10 minutes, an hour, and overnight. I pleaded. I threatened. I cussed. I begged.
I did not try poking any objects into the CD slot to retrieve them. I didn't know what the unit looked like inside the slot and didn't want to create a second (bigger) problem by poking blindly. I also felt it was likely the problem was a CD warped by the summer heat. I figured any object thin and long enough to fit through the slot was probably going to tear up the edge of the CD if it could grasp it firmly enough to pull it out. Not to mention the stuck CD might have been at the same level as the opening.
The CD's still didn't come out easily once I had the unit opened. I really didn't want to ruin the CD's. I disassembled the unit one piece at a time until I could remove the disks without forcing anything. I photographed everything once it was apart in case I needed to ID any components or use any of the serial numbers I found.
1) As far as "syncing the mech" goes, I didn't do anything beside disassemble the unit, remove the CD's, reassemble it, and replace it in the Envoy. I had done this once before a couple of years ago without problems.
What do I need to do to synchronize it? I'm assuming you mean the CD loading mechanism has to be at some "home" position when power is restored. I haven't a clue what position the mechanism was at when I took it apart or put it back together. Whatever you call the mechanism that moves the CD around is the only part of the unit I didn't disassemble- I removed the unit from around it. I would hope it's in the same position it was when I took it apart, whatever that was.
Even if the loading mechanism is out of sync now, what caused the original problem? I don't know, but I'm guessing it didn't get out of sync while it was safely in the dash, away from my prying fingers and tools. The CD icon is still blinking everytime I get in the vehicle. Now the icon stops blinking after I push the insert button, where it didn't stop blinking previously. The insert sequence still doesn't work. It recognizes (correctly now) that there's no CD's in the unit.
The CD's all looked OK to me. I haven't tried them in any other CD player yet. My guess is the unit has an electrical or mechanical problem, or both. Is there any testing I can do to troubleshoot the problem? This isn't my career field, but I'm pretty mechanically-inclined- overhauled car engines growing up, fix washers , dryers, microwaves, etc at home, rebuild computers at home and work, etc. If something is fixable with reasonable costs, I can usually fix it.
Oh yeah, I've got a DMM and a hammer. Any suggestions would be greatly appreciated.