The repeat until it sticks part sucks.  I was working with someone on an allroad mt swap and the shop re-coded it, but I think chose the wrong brakes.  Tried changing the coding but gave up after several attempts of it not sticking.  Not sure if we were using the wrong login or what.  Is there any indication in VCDS if enter an incorrect login?

Also, the login... is that based off of what the coding used to be, or what it is now?  Does the login remain the same from the factory regardless of the coding?  Or does it dynamically change based on coding.

It would be nice to clear up these questions.

This was a help to me WRT to the ABS module.

http://wiki.ross-tech.com/wiki/index.php/Audi_A6_%284B%29_Brake_Electronics_%28Bosch_5.7%29

It's very specific. What I do is as follows:

Clear codes. The incorrectly coded will remain. That should be the only one. If you have failed a login, and have a DTC that says "Check DTC memory of engine controller" Do that. Clear the engine codes, then go back to ABS. Clear the codes in ABS.

Login with 07495.

Clear codes again.

Go to coding. Change the last digit from a 7 to a 5. Press do it.

If the coding has changed, excellent. If it hasn't, repeat the above steps. Sometimes I alternate between 07495 and 07497 as login codes, only because I get frustrated and want to kill something.

Eventually, it works. Sometimes takes one try, others 5, others 20, but it ALWAYS works. After the coding sticks, clear the codes again. Then, do an SAS alignment and you're good to go. If you skip the alignment, when you turn the key off and then back on the coding may revert. Noone wants that.

You can code the ABS manual with the ecu auto or manual, with the tcu in, or out. It's just a fickle bitch.

I have tried everything except clearing the codes while logged in.  I will try that tomorrow.  I am not sure that I actually get logged in.  As soon as I clear the code it comes immediately comes back. 

18034 Powertrain Data Bus
           P1626 - 35 - 00 - Missing message from TCU

Thanks for the suggestions, hopefully I can get it to stick.