[urq] Need to Get a Specific Electronic Speed Signal From an UrQ Speedo......

[Steve Eiche]

Patrick,
On the MB and RR the diff lock, and radio GALA ARE definitely connected 
in parallel.   It is on the RR and MB schematics and connected that why 
in the factory RR harnesses that I have.  I'm not sure why you saw the 
behavior that you have.  ETKA says that there is only one diff lock 
module - 893 919 173, that is shared by all the cars with electronically 
controlled diff locks.

I have no BTDT on the 7A ECU signals.  All I know is the I5 turbos and 
later ME5 cars.

The fuel consumption signal on the RR (and I would bet 3B as well, as it 
is virtually the same ECU), goes directly to the dash.  It is a DC level 
I believe, that mimics the behavior of the old throttle plate pot 
wiper.  I believe Martin P. confirmed that the 3B ECU fuel signals 
worked with the CGT digi on his Euro '85.  I don't know much about the 
7A signals, but I bet that they would be the same.

Hope you guys all wrote this stuff down.

Steve Eiche
Shade Tree Software, LLC
http://www.shadetreesoftware.com
seiche at shadetreesoftware.com
800.419.6896 ext. 902
303.940.2468



Patrick Carlier wrote:
> Steve ,
>
> Interesting stuff you send here .
>
> I do agree that the diff lock , radio GALA , CC etc are in parallel .
> But the VSS signal is coming from the instrument cluster , not
> from the speed sensor . That is according to the wiring diagrams I have .
>
> I can also agree that the reed contact should be capable of driving 
> the digital dash .
> If it's internally pulled up to 12V . Quite possible .
> Maybe I should have tested it before I modified my six speed gearbox
> to receive the old sensor .
> Never bothered , as the mechanical conversion was easy enough .
>
> About the dif lock .
> I tried feeding the ur-q speedsensor signal directly to the diff lock 
> unit .
> Diff lock unit was taken from a late 20Vcoupe quattro , not from an 
> ur-q !
> And that gave the behaviour I described .
> Possably , if there's an ur-q diff lock unit available , wich I didn't 
> knew ..
> Maybe it is a different part number then the 20V unit I'm using  .
> I know for sure the cc controller is different for the early and later 
> style cars and I
> assumed it had to to with the difference in speed signals . .
> Didn't have the lock switch input wrong , can't be cause the switch 
> itself is still functioning .
>
> And on my ecu ( 7A ) the VSS doesn't seem to influence performance .
> Except for an occasional stall when I return home from a high speed 
> drive .
>
> Do you know what teh fuel consumption signal from an ecu ( 7A or 3B ) 
> looks like ?
> I have the fuel consumption gauge on my digidash not functioning causi 
> I rpalced the k-jetted engine
> with a 7A . And I don't have the K-jet metering plate sensor anymore . 
> And I didn't dare connectiong
> the ecu signal directly to the dash input . Any btdt on that one ?
>
> Pat
> 1981 Ur-q 100% original , full option
> 1981 Ur-q 3B and Six spd .
> 1986 Coupe Quattro 7A and Six speed , daily driver .
>