Car Battery Replacement - Key Fob Issue

[b5djm]

I have just bought a Boxster - 1998 model - took possesssion, today.
Dealer put a new battery on car for me today. But then key fobs have stopped working (dont know if they were working or not beforehand)
My problem: Will lock car with key, but when unlock car, then alarm goes off.
One key fob flashes fast. The other key fob flashes slow!
There is only a lock / unlock option on these keys - do I need to resynchronise these keys - or could my problem be deeper routed?
Its a 2.5 Boxster
I have read various methods of reprogramming but none of them work (some have been utter rubbish to be honest)
cheers
Dennis

[ekam]

Replacing battery should have zero effect on the programming of the key fobs... Did you put fresh batteries on them?

Worse case scenario: If you bought it at the dealer they should be able to reprogram for you, provided you got it at a Pcar dealer that is.

[pjv]

Disconnecting the battery had no effect on remote key operation with my car, so I don't believe that a new battery would be a problem.

If you open the door with the key instead of the remote fob, the alarm will normally activate after 10 seconds or so unless you insert the key in the ignition and turn it to the first position.

I find that my remote key fobs do not always work, even though the lights flash when I press the button. They seem to be more reliable if I stand a bit forward of the windscreen, so try that. You could put a new battery in one of the fobs to see if that helps. Otherwise you may have a more serious problem.

Also, my keys only lock/unlock, I don't know if any other options are available.

Hope that helps.