Article from someone that got ccs working on an Audi A6:-

Hi All

'98 Audi A6 2.5 TDI in the UK

I'm happy to say it's all working now. With a little preparation it took me a little under two hours from start to finish. I may do a step by step guide in the future, but for now here are some part numbers and pin assignments that were used:

Cruise control stalk for my car is 8L0 953 513 J0 1C
10 pin connector housing that mates with above stalk is 8L0 972 980
new spline head bolt for steering wheel (to be safe!) is 907 991 01

I did not order any wiring, as I didn't know what to get - but I've now found that the flat connectors that you could use are from single wires part number 000 979 003 - you will need 3 wires for a total of 6 connectors. However I just soldered the wires straight in with no problems.

You need to run a total of 5 wires - 4 to the e-box in the plenum chamber, and 1 to +12v - i used terminal 30 under the dash. The wiring diagrams from Audi call for Terminal 15 but I don't know where that is. I don't imagine it's a problem having this line high all the time, but to be safe you can just turn CC off.

In the e-box there is a big white connector that comprises two connectors, a 3 pin and a 15 pin. If you unplug this you will see that there are 4 wires going from the ECU that don't have pins on the other side, and thus are not connected. These are the CC lines. Pull them out of the housing and plug the connectors back in, so you have 4 wires free. The colours are:

blue
red/yellow
black/white
red/grey

Now, the pin assignments at the cruise control stalk end:

2: blue wire in e-box
3: red/yellow wire in e-box
4: black/white wire in e-box
5: red/grey wire in e-box
6: terminal 15 (+12v)
7: black/white wire in e-box

As you can see both pin 4 and pin 7 are connected to the black/white wire. I just looped a small wire from 4 to 7 and just connected 7 to the black/white wire in the e-box.

When I'd wired it all up, I used VAG-COM to log in with 11463 to enable CC, then I went to measuring block 6 (I think - I'll need to check this) to monitor the bin bits for CC. I got 0's changing to 1's in all the right places when I operated the new switches. Success!

Put everything back together, and went for a road test - again, no problems, all functions seem to work.

Now I will go and put my air-bag back on, and see if I can retrieve my screwdriver from the engine bay, but I fear it is gone forever!