My audi a4 avant remote central locking has stopped working. Something is draining the battery on the car,not sure what yet as I've not been using the car unless moving it to get in the garage after jump staring it. Won't be driving it for another 2 weeks so have got it hooked up to an optimizer,which says the battery is fine,every else seems to be working fine but for some reason the remote central locking isn't? Anybody any idea if its a common problem and what it could be? Thanks in advance.