Anyone doing a console change and fitting the newer switches with the round buttons will come to the ASC switch. The old switch has a different connector and in the back of the switch you will see 6 pins in 2 banks of 3. The new round button switch has only 4 pins in a line at back of the switch, and therefore the "old" connector will not fit. First off you'll have to find a suitable connector with 4 in a row female ports. Next, the switch pins on the new switch are numbered 1 - 4.
P.1.......Power (from Fuse 21) Green Blue Yellow wire.
P.2.......Earth. Brown wire.
P.3.......Dimmer light power. Grey Red wire.
P.4.......Contact to ABS/ASC Module. Blue Violet wire.
That will sort out the re-connection in the correct positions for the new switch.
The 4 pin connector is available from and can be ordered online at:- http://www.mouser.com/catalog/catalogUSD/641/1387.pdf
4 pin connector part #......571-1022412 ($.1.33) - You need 1 off.
4 x locking connectors to fit on the ends of the 4 wires...Part # 571-876673 - You will need 4 off ($0.31ea)
BMW do not supply these items, and consider them to be part of the wiring harness.
Mouser electronics carry a huge range of stuff, and may be of interest to others who are interested in such stuff...