Originally Posted by putsjunior
Could it be a dead battery and the lock cylinder is electronic?
Yes to both. If the battery is dead or has been disconnected, you still can't unlock the doors even with the key. You should be able to unlock the trunk with the key but that won't help you gain entry to the car unless you have the rear seat folded down. Otherwise your only choice will be to call an approved locksmith to break into the car using "specialist tools".