Porsche Repair Questions? Ask a Mechanic for Answers ASAP
Did the key work before the battery went dead?
Does the remote control function work on the key you are using?
do you have another remote/key?
If the alarm is going off right now, wait until it shuts off (3 minutes). Then try to unlock the car with the remote. Or lock/unlock the car with the remote.
Does the key go into the ignition?
If it does go into the ignition, do you hear a definitive clunk from the steering column?
Any warning in the instrument cluster?
One more thing:
Does the ignition key/remote that you have unlock the drivers door handle lock cylinder?
The remote has a small transponder glued into it to perform the immobiliser functions. It tells the steering column to unlock the steering column and allow the engine to start. It sounds like either this remote was never programmed or it lost it's programming. It happens but to attempt to recover this key, you will need 3 codes that are only available from the dealer and also a PIWIS tester or equivalent device that could be used as a passthru to program the key. I know it is not the solution you want to hear but it is the truth.