The default code you mentioned, is not accepted, if the code has already been changed.
The keypad is in lockout at the present, due to four failed attempts.The keypad becomes active after the lockout timer ends (usually a minute or so).
You need to return the panel to factory settings,reprogramme the panel, and learn in all wireless devices.
This procedure is in the manual,its done entirely with the keypad, and doesn't involve any links,unlike most GOOD panels out there.
My only concern here is with the battery removal and power up procedure,therefore I suggest you remove mains power from the panel, before!!!!! you remove the cover for battery access.
The reset procedure is defo in the manual, and can be downloaded in pdf form.Good luck with it and if you run into any problems,get back to us.
e manno
May 2012