Scantronic 9751. 9941 Keypad: Amber Pulse Warning Triangle light

Hi, after what I believe was a power cut, my panel went completely dead, I replaced the 12v battery for my 9751 Scantronic alarm as well as the 13amp fuse going to the box. I did NOT conduct an engineer reset via the shorting of the NVM and kick start pins. I thought the mains would charge up the new battery and the panel would come alive. However the panel lcd stays dead but I keep getting the amber light on the warning triangle repeatedly pulsing quickly. Any help getting this up and running is much appreciated. Thanks in advance.

Jay, November 2021