Catware

I have an A4 with 89k miles, which has the central trip computer on the instrument cluster, and the display is bad. I purchased a new instrument cluster on eBay, but unfortunately it was NOT new and had 35k miles on it, although its central display is perfect. I need to change the miles on this new cluster. I successfully connected a function generator to the pins on the cluster to feed it a speed signal and increase the miles, but I am looking for a more elegant solution.

I identified the location and model of memory IC on the instrument cluster PCB, which is a surface mount STM 93C66. I purchased new 93C66 ICs, assuming that when the clusters' boards are assembled and the clusters are given power for the first time, they must initialize themselves somehow. After desoldering the IC and putting a new one in its place, unfortunately the cluster is not working properly -- the central computer does not display anything although the mileage is indeed set to zero. I am also getting garbled info on the Vag-Com interface 17 page. And, the cluster thinks its workshop code is 131071 and is resisting attempts to change it.

Anyway, I could of course purchase a microcode EEPROM programmer to change the values in the original EEPROM but I am wondering if perhaps VAG-COM can access it so I can get this done without having to wait for the programmer to arrive. The car is a '99 A4 without immobolizer, without CAN bus.

Thanks!

Uwe@Ross-Tech.com

Nope.

Catware

...it was very unlikely. I just thought I'd ask before ordering the EEPROM programmer. Thanks!

Uwe@Ross-Tech.com

Since you apparently have the skills, why not just take the EEPROM from the bad cluster and put it in the good one?

I.e. why do you want to duplicate it?

-Uwe-

Catware

I am beyond trying to find a solution for my initial problem (which I already got with using the function generator). Now I am merely curious about the cluster and wanted to play around, since I have one cluster that is otherwise going in the trash.