Hi.
Perhaps it works for some of you... Pull the CD changer assembly out to a work bench.

- When bought (used vehicle) the CD error was "No disc"
Fixed by re-soldering 2 surface mount microswitches found intermittent at both sides of the black plastic lever that fits between them. It was preventing from loading the disc from the cartridge to the reader assembly.
You should have good hand skills and a small soldering iron, and short heat application time. Need to remove only the top cover 4 screws for the surgery and you will spot them. OK

- The CD audio did not come out at left doors, radio did fine.
Partially unplugged CD changer connector in the back of the radio. The radio extraction tool is needed to reach it. Pushed in all the way, OK

- "CD error" message, and cartridge cannot be spit out.
Found a disc and its individual tray bitten by the reader assembly 'elevator mechanism', as seems the elevator mechanism came one step down too early; the disc that was playing last had not been stored into the cartridge yet.
Pushed both the disc and its tray painfully slow and hard enough without bending/damaging anything.
I saw no other way to do it. The cartridge would never come out in that failure. OK
Need to remove only the top cover 4 screws for the surgery.

Good luck !