what size is the remote battery? the one in your key the battery

 

its a really common size just take them out and go to any store

 

will replacing hte battery imporve the distance that the buttons work, cause min is only like 20 feet, if that

 

Your lucky, mine only works if im less than 10 feet from the car. I even measured, after 10 ft the remote will not function...

I hate it, and I just bought 2 keyless entry remotes, and they cost me almost 200 for both from Audi, i should have just gotten valet keys....

 

cr1620 3V i believe

 

to get better range put the remote up to your chin when you push the button it seriously works 100x better