I am going to fit a Timewise Rally Computer to my '07 MZ4 Coupe, and I need to know whether it throws off a Vss signal, or whether it has only a CAN-bus signal to replace the Vss signal used by the electronic speedometer. Can you help me with this?

There is a traditional VSS signal in the cluster harness: pin 6, green/yellow. Also at the ABS module in the bay, pin 10, same colors.

There is also a can bus square wave that feeds the radio for the dynamic speed - volume changing functionality (its a black/white wire, don't know the pin offhand), but I recommend the vss for more accuracy, down to 0.5mph.

Thanks a lot Reach! That sounds like what I need to know.