Can anybody tell me how to get something working in PSS...

Can anybody tell me how to get the FMC and the digital display (which shows the bank angle etc.) to work when were about to go in the PSS Dash-8-300?
I start off with engine off only, and then when I start up the engines the displays dont come off. I've also tried restarting and turning off the engines continuously, but still they dont come on??

Any help would be appriciated.