I need a little help. My key, not the gray one but the big black one that unlocks the doors, has stopped working. I replaced the battery with an Energizer battery that has the same numbers on it as the original Panasonic battery. Nothing happens. It won't lock, unlock or panic. Is there something that I should do after replacing the battery? Manual unlocking was fine until the little door that covers the lock hole froze shut last week so I need to get this thing fixed. can someone help?