i've got the same problem..
i changed my battery in my key, and still not working..
disconnected my car battery to start fresh,, and still nothing.. soo not sure whats next??
my alarm has been draining my battery a lot though? like after a couple of days of not starting, it had that dying sound...
atm i have the alarm fuse out, since then no drainage haha,,
any ideas? could it be something with the key? or something internally with the car,,, is there any way to check if the key is working or not?