The set does not come with a dcs/dcc switch, but after asking mth about setting up the r142a subway to run under dcc they provided me with these instructions. I followed them and it works. The only thing I would add is to make sure to differentiate between that grey cable and the one of the proto couplers as they are the same type of cable. Also, you may wanna install a small switch as it is a better solution to the wire nut. Hope this helps.
