[mk1vw]

trying to ID pin 64, it's a solid purple(or violet) color wire.
the A2 resource is pretty good, but it shows pin 64 as empty.
http://www.a2resource.com/electrical/management/motronicvr6aba.html

wire is actually dark purple with black stripe, bad choices for contrast..

 

[mk1vw]

oh well, car runs fine with the wire not connected.
i guess it will remain a mystery.

 

[dubCanuck1]

FWIW, it goes into the gauge cluster under T28b/3. Still researching on WTF it actually did. Bentley just says "1-pin connector" when you look at the ECU pinout. The gauge cluster doesn't have it's pin shown either.

 

[mk1vw]

thanks for that. I'm not running the original cluster so this wire will dangle.
I'm actually doing a swap into a MK1 right now, this project was on hold for a long time..
looking for an ABA OBD2 ECU pinout now..