So I've read many posts but haven't seen any pertaining to my problem. So if this was covered I'm sorry. I have an 2001 Audi TT roadster.

So the issue I'm having is my alarm won't arm or disarm when pressing the buttons on the remote. I can arm the car if I insert the key into the keyhole of the drivers side door and turn the key towards the trunk twice. The alarm will activate and the horn will beep once and the alarm light in the door will blink. And I can unlock the drivers door with one turn of of the key towards the front of the car and twice to unlock the passenger side. I have checked the fuses and replaced the batteries. I also tried to rekey the key with the instructions in the manual and other ways found on forums but that hasn't worked.

I'm not sure what else to do other than pay the crazy fees and go to the dealer.

 

Do you have a second key?

This was on another forum:
1# you take one key put into ignition turn on.
2# close door, lock it with the key hole on driver side,with the key you want to program.
3#once it's locked, press the open button once or 2 or 3 or 4 times depending on which key is being reprogrammed (you will see your side blink every time you press ,wait 6 secs press again once)
Your car can have multiple keys, and each time you press the button you are selecting which "slot" the key will be linked to.
#4 Take the other key in ignition out.
#5 Close the door and try locking with the reprogrammed key.

Also, make sure you don't have anything plugged into the ODB II port. I believe the antenna is there and when I left my Bluetooth ODB II sensor plugged in the key fob ceased to work.

 

I had the same issue and took it to the dealer. They said it was the comfort control module. I haven't had mine fixed yet

 

I just ran into the same problem. No more beep when I lock it with the remote, and no flashing red light. Anybody got a fix?