Scantronic 9651 won't reset?

I'm having a problem with my Scantronic 9651. The keypad is showing Ver 4.00 Feb 15 2007 but won't accept entries to get to installer mode.

I installed my 9651 a few weeks ago and all worked fine. I added an extra PIR today and as I closed the panel I accidently pulled out the external bell tamper return. The external bell went off and would not stop even when the TR wire was replaced. I had to pull the mains and battery and then reconnect to get the external bell to stop.

However since then, the keypad only shows Ver 4.0 0 Feb 15 2007.

I've tried various power up methods, removed extra keypads, removed the new PIR and still the keypad only shows this.

The keypad buzzes on power up and stops after first number entered. The keypad allows me to enter 6 numbers only (which don't show on the screen) and after that it just bleeps every time I enter another number.

I'd like to try avoiding doing an NVM reset if at all possible.

One extra bit of info, the internal 660 dialler is continually dialling out since I pulled the bell TR. I've had to temporarily take off the communicator connector to stop it.

Any help would be greatly appreciated.

s1myr
August 2012