Key What should I check to resolve my remote key issues? Both keys to my 2003 Audi TT work manually but they do not work remotely. I have replaced the batteries a couple of times and followed the reprogramming steps. They work again for a couple of days and then stop working again. Any suggestions?

SOURCE: Key programming

There are two different programmings being spoken here...
1: is the "safety interlock" it's a security measure. if you go to start the car and a Yellow key flashes... that is the interlock security system. If you don't have a key specifically programmed for that car's VIN, it won't start. This can only be done at the dealership, and yes they charge about a hundred dollars. The price is the same for 1 or 10 keys for the same car. Some earlier audi TT's don't have this feature (including some 2001's). If you want one key reprogrammed to work, you will need to have ll keys reprogrammed. This programming is put into the switchblade's half of the remote. (if you pull the key apart there are 2 pieces, one that holds the metal switchblade key, andone that has all the remote buttons) a key without buttons is commonly called a valet key, which also needs interlock programming to work.

2: The keyfob's remote buttons. Lock/Unlock, Trunk open, and Panic. These need to be programmed by the dealer as well. They charge $50-$100. The price is the same for 1 or 10 keys for the same car. This programming is put into the half of the remote with all the buttons (the keyfob). This is not a necessary feature to operate the vehicle.

SOURCE: Program a remote key for 03 A6

I have an A4 and did this to re-program my key:

1. used the key to start the car...then turned it off
2. put the key in the driver door (door closed)
3. pressed the lock button on the key fob once
4. turned the key to lock the door.

This is basically the steps in the owners manual, but the car must be started with the key first, and the key must be in the door lock before pressing the lock button.

SOURCE: My infrared remote does not work. I have an Audi A6 1995

Do you have memory seats as well? If so follow these steps I am going to refer to the keys as A and B as you have 2 of them
1) Unlock car with key A
2) Turn ignition into ON position with key A and roll down the window
3) Point Key B at IR Sensor and Click twice (perform both clicks under 5 seconds)
4) Turn off ignition and pull Key A out
5) Turn ignition into ON position with Key B
6) Point Key A at IR Sensor and Click once
7) Turn off ignition and Pull Key B out

Key A should be programmed as the Master Seat Program and Key B should be programmed for the Secondary seat program
So when you set your memory seats Key A is for Memory Position 1 and Key B is for memory position 2
if you don't have memory seats then you only have to point the receiver at the sensor and click once. That should just sync the IR Frequency and Codes

SOURCE: Audi A6 Anti Theft Central Locking Tantrums

Sounds like you are having problems with your built-in alarm system. Like most systems in your Audi, you can read the error codes stored in the controllers. It takes a tool normally only a dealer has (VW or Audi) or an adapter like the VAG Com. (Google it)

I also think you can disable the alarm system and just use the key.

Could the lock button on your remote be stuck? Use a different key/remote. (leaving the suspect key at home.) The keys/remotes can be taken apart....

SOURCE: central locking will not work on remote key.

unlock car with key/hold over for 30 secs then lock car with key/hold over for 30 secs then unlock with remote hold button down for 30 secs.this should reset system.