I have code E showing on my Scantronic 9827 pad Can't activate alarm?

Scantronic 9827. Having changed the battery I tried to activate the alarm but pad display shows E. I have attempted to re set the system using the manufactures code without success. I had a similar problem some years ago (not replacing the system battery) and used the code ~~0789099 which worked . The ~~ represent other symbols, for security reason I have not shown them.
I would be very grateful for any advice on how to remedy the problem. As far as I am aware the system is not in engineer mode. Thank you