A quick search of the forums didn't reveal an existing thread for this one...
I've had my 2007 A5 3.0TDI Sport for about 3 weeks now. Just this week, when leaving work, tried unlocking with remote fob, but the car was dead... nothing... zip... nada. The LED still flashed on the remote but no action from the car at all. Even tried lock and boot release, still nowt. I unlocked the car using the key hidden in the fob - the car started fine, and when I switch off the ignition the remote worked again! Just put it down to a glitch at time.
However, it happened again yesterday at the exact same time (leaving work). I replaced the battery in the remote fob prior to the 2nd failure, so I know it's not the fob battery.
Last night I switched to my 2nd key, so we'll see how that goes.
It seems a strange thing to happen, being fine for the first two weeks of ownership, then failing twice in three days in the same spot. I initially wondered whether it was maybe to do with the amount of time the car had been standing, but it's never (yet) done it in the morning after being left overnight which is even longer.
Anyone have any experience of this? It's a little worrying because I know if I whine to the dealer about it, they'll have a look but unlikely to find anything because it's so infrequent (but bl**dy annoying nonetheless).