britquattro

I've transplanted a 4.2L ABZ into an UrQ...runs fine with the A8 dash cluster, but I'm interested in switching back to the original dash cluster. All I'll need is a speed signal for the ECU. The speed signal coming from the transmission is the same, I believe, between the later UrQ with a digidash (electronic speedo gear drive)and the A8 with essentially the same speedo gear drive unit... but after the signal enters the A8 dash cluster to drive the speedometer something happens to the signal ... the cluster somehow modifies the signal it then in turn sends to the ECU. Does anyone know anything about the signal modification, or how I might recreate the correct speed signal without the need for the A8 cluster and its associated electronics? Any help is greatly appreciated.