how can i fix my9651 burglar alarm system?

You could try the default engineering code,but no guarantees here,

enter 07890

enter 99

press tick icon twice,

If she won`t reset,the default code has been changed.

You also need a new control panel backup battery,please ensure you remove mains power before you attempt a battery replacement.
Try the reset first,replacing the battery at this stage doesn't affect the reset.

e manno
May 2012