Resetting Keyless Entry System
 

I recently went on a trip and left my 996 locked for more than 5 days.
On return, I entered with the key but neglected to reset the system with the key fob before opening the door.

Nothing I could do would reset the system.
Yes, I know. Two beeps, three beeps, ignition off, ignition on, standing on right foot while holding fob behind my back. Nothing worked.

Faced with a visit to the local stealership, I did the unthinkable - I disconnected the battery.
That reset the system and all went back to normal.
Interestingly, a 30second disconnect didn't do it. I found I had to disconnect the battery for a long period - a couple hours as I had other things to do - before it reset.
Although I had to reset the clock and re-enter the radio code, everything else remained including the radio presets.

I hope this saves someone else a few bucks.