type 89 speedo data information?

[Huw Powell]

>>I have two busted odometers, and want to try to fix one "on the bench", 
>>which would mean needing to synthesize the data stream from the sender 
>>in order to see if I've succeeded.

> Here's the problem - the speedometer (I put the needle back on to test 
> it as well before further reassembly, a neurosis of mine, to test at 
> every step...) is not reacting.  I've done some measurements and 
> testing, making it seem even odder.

Well, I found half a solution.

Discovered that the speedo module can actually be removed from the back 
of the odometer.

So I pulled the cluster from my car, dismantled it as per the endless 
process, and pulled the speedo needle as carefully as I could (hoping 
that is not what broke the old speedo).  Popped out the speedo module 
and installed it in my repaired odo thing.  Slowly reassembled piece by 
piece, testing as I went.

It's now chugging away on the bench, I'm trying to decide if running it 
at 120 mph for almost 3 days is worth it, to get those "bragging rights" 
miles the clock missed while it was broken back on there.  Not sure if 
276 versus 285 k miles really matters, except for that big thrill of 
hitting 300 k sooner.  All I know is one of my Audis has been to the 
moon and the other one drove back.

Not sure what "broke" on the speedo I hurt, but since the "return 
spring" isn't working right I think I may have accidentally hit it with 
12 volts along the way.  The return springs are actually the two 
conductors for the speedo voltage, each one resembles a little watch 
mainspring.  I might have cooked the temper out of them, and perhaps 
also screwed up something else along the way.

Anyway, it's been fun chatting with myself here on this thread.  Just 
wanted to leave my (almost) conclusion, that these things are quite 
repairable, the Southern Electronics gear is the right one.

Maybe I'll bag that 9000 miles I'm missing and reassemble for a test 
drive so I can finally wrap things up.

-- 
Huw Powell

http://www.humanspeakers.com/audi

http://www.humanthoughts.org/