My odo hasn't been working for a while, but the speed counter works fine. Last weekend I bought an instrument pannel from a wreakers, I installed the speedo unit into my instrument pannel, the speed counter worked but the odo didn't. To see if it was a problem with the intsrument pannel circuit board I swaped the instrument pannels - and got the same result. The instrument pannel I got from the wreakers wasn't in mint condition - the fuel and coolent temp gauges also didn't work. So I'm left with a coupe of possibilities 1) the speedo unit I got from the wreakers is also faulty or 2) that the problem lies outside the instrument pannel. I think it's probably 2.

I thought that the speedo unit simutaneously calcutaled the speed and distance travelled by recieving electrical pulses - is this correct?

Does anyone have any ideas on what the problem could be?

 

Audi's did have some sort of a problem with the electronic speedometers. Go to www.sjmautotechnik.com and go through the diagnostics link, there might be a fix.

 

Audibaby, I had a similar problem with my 80. Occasionally the odometer would stop, although the speedo continued to work properly. I used to zero the trip, and the odo would start up again, but it got progressively worse, and in the end was mostly out of action, and zeroing got less and less effective. I need the odo, so, like you, I acquired an instrument cluster from a scrapyard, similar mileage (165,000), and changed the speedo unit. It is now OK. This must be a common fault, so perhaps you were just unlucky with the replacement. I haven't yet checked out the site recommended by Offramp, but I hope you have success with your problem. Bryan. PS. I will be posting a problem I am experiencing, so if you have any ideas, I would like to hear them. Thanks.