CD Changer Jamming in UrS4/S6

CD Changer Jamming in UrS4/S6

I had a situation where two CDs left the cartridge and decided to impede the changer mechanism. You can probably guess who won (no one, the CD’s were shattered and the unit quit working). The first problem was that after the unit seized I couldn’t even get the cartridge out to discover that there was a disc problem.

I’ve yet to figure out exactly why it quit – unit detected problem and a safety shutdown, the changer drive mechanism overheating, or…..

What I did:
0. First objective – restore basic power to the unit so that I could eject the cartridge.
1. Looked for any unique fuses for the CD assembly – none were found.
2. Reset connector cables to the changer assembly – no effect.
3. Removed the CD Changer assembly from the trunk, removed the cover from the changer, removed the cover and base plate exposing the internal mechanisms, protected by plastic sheets that were semi-transparent.
4. Removed the disc remains.
5. Looked for any loose connections, obvious PCB breaks or components broken by the CD coming apart – none found.
6. Reset two ribbon cable connectors to the base plate, reset the internal power cable connector, etc.
7. Reassembled the unit – no luck.
8. Checked with Audi for the price of a repaired unit – ~ $300, but no units were available.
9. Called about the ads in Quattro Club newsletter – $595 for a whole unit (less head), and none immediately available.
10. Looked for conventional units to replace the changer altogether, looked at Sony since that seems to be who manufactured the unit for Blau. who then seemed to design and add the interface unit, put an Audi sticker on it, and at least double the price. Decided that my only option was a complete replacement – also pricey and time consuming.
11. Repeated steps 3 through 7 again, this time using contact cleaner on the connections and putting a multimeter on the connector plugs to ensure power was getting to the unit (I can send a copy of the wiring diagrams if you’d like them). This time the unit worked after reassembly, and has been working for the better part to three months now (as I shrink waiting for bolts of lightning from the Audi Gods!!!).

Observations:
1. Not even AoA has good diagrams or diagnostics for the 10 disc unit. The best they had available at the dealership was a warning not to use the Alpine diagnostic procedure as it would damage the 10 disc unit. This was on a sheet that said AoA was in the process of creating the 10 disc diagnostics. The date on the sheet was 1992 or 93 as I recall. When pressed in October 1997 the best that AoA could produce was the wiring chart showing chassis connections, but no diagnostic procedures.

2. This appears to be a questionable system. While I don’t strongly object to the music quality of the Audi Bose (it’s one heck of a lot better than the OEM system on my 86 4KCSQ), I’d think that there would be better ways to diagnose and support the customers.

3. Awfully expensive for what you get!

Bill Fuson