These days newer cars have built in universal remote which is very convenient and COOL. Our new (used) 2004 Cabriolet does come with one and I had to try to program it for our garage door. The new garage door unit these days have security feature built-in called rolling codes (Genie) and it needs to be paired up with each new remote. The programming on the Audi has been painless (Q7) and the homelink systems work better than the original remotes that come with the garage unit. This Audi A4 is no different, painless with a twist .
According to the manual
Turn on the ignition, press the button # we want to program it to, wait until the red LED indicator starts to blink slowly. We have 5 minutes to program this button.
When the LED starts blinking slowly, take the working remote, go in front of the car and press the remote to open/close pointing at the bumper (actually in our car, we can sit in the car and press this button and it still works), hold the button until the signal lights blink 3 times, then release the remote button.
Now, when we go back inside the car, the slow blinking LED turns to fast blinking LED then OFF. We press the button to see if it works, but it doesn’t. We need to go to the garage main unit receiver, there is a “learn” button with a red LED indicator, we need to press this one, the red LED indicator will blink slowly, now go the homelink button and press it (1 second interval) 3 times, the third time, the garage should open/close. We’re done. Take the car out, drive away from the garage, press the homelink button to see the range, our Q7 and Cabriolet are pretty good. The twist is that the spare remote that I used is no longer works after the successful programming of the Homelink system. I can only choose one or the other and not both. Something is going on between these 2 transmitters. There are no codes switches inside the spare remote for me to even try to change it.
Video tells the procedure better