jgerwitz

I was working on the Autocheck system of my '92 100S last week and I must have caused a problem with the Tachometer. If I remove the instrument cluster daughter board, the tach works fine. With it installed the tach needle may jump a few times and then stops at the bottom. I did fix the autocheck display though. I had to resolder some of the connections on the daughter board. Does anyone have an idea what the problem may be or know of a source for the schematic for the instrument cluster? I have the complete wiring diagram for the car, however, it does not include the IC schematic.

EDIGREG

These are the instrument cluster wiring diagrams from the Bentley. Tachomoter is on page 28.<ul><li><a href="http://dgreg.phpwebhosting.com/audi/icwiring/">http://dgreg.phpwebhosting.com/audi/icwiring/</a</li></ul>

jgerwitz

Thank you for your reply, however, I do have the factory wiring diagram for the '92 100S. The manual doesn't show the component level schematic of the IC and Autocheck system. Do you have any other ideas if I can't get a printed circuit board schematic?

Thanks again.

Audi Logic

the tack only has four connections,so the issue should be fairly easy to find...
check the places you soldered to see if any contacts are bridged

Fair Cape-Cape Town

Print those out and paste them together. Its complete and there is no better anywhere else.