Speed sensor X1BT - Fitting to 2002 Mercedes Sprinter

[UncleSteve]

Please be nice to me as I'm very new to my X1BT

 

I've almost sorted the wiring of my X1BT, however I'm wondering what to do about the cable for the speed sensor (SSC) on the 'hide away unit'. What effect will it have if I do not wire it up?

 

If the SSC is a 'must' does anyone know where to connect it on a Merceds Sprinter 313 (2002 UK spec)? I have looked at various manuals and sites, but they've all left me confused.

 

Thanks in advance