type 89 speedo data information?

[Huw Powell]

I am wondering if anyone out there has ever analyzed the signal that 
drives the electronic speedometer/odometer (the late coupe and various 
type 44's are probably similar).

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.

So, anyone know... frequency to speed ratio; nature of signal - square 
wave, sine wave, duty cycle if assymetrical, etc.?

-- 
Huw Powell

http://www.humanspeakers.com/audi

http://www.humanthoughts.org/