[V6-12v] 2002 A6 Turbo Key Problem

[C. Izquierdo]

I have a 2002 A6 Turbo and had to change the batteries in one of the 
master keys.  Now that key still does not work.  I have tried doing  the 
synchonization explained in the manual - press open or close and within 
one minute close or open the door - but that does not seem to work.  The 
dealer. over the telephone, tried to walk me through another method -

1- use one key and turn ignition without starting the car
2- using other key lock the car
3- press "lock" near front side fender marker
4- wait 10 seconds - press "lock" twice
5- put key in door and try to open

This method did not work, or when it did, it worked only for one key.  
When the process was performed for the other key it seemed to reprogram 
the whole system so that the key in the ignition was not included.

Does anyone know the correct sequence for doing this?  Thank you.