ESL 2500 FACP

Hi Everyone,
In an ESL 2500 FACP, does the main control board need to be connected to the power supply board for the power supply to put out voltage?
I have a power supply thats burnt up, possibly lightning, bought a replacement from ebay and still not working. I do not know if the main control board has an issue, but I am not getting anything out of the power supply. 120vac is good. There is a multi pin connector from the pwr supply to the MCB along with the 24vdc connection. Is this multi pin connector some sort of control?
No schematics and the manual makes no mention. Any help is appreciated.