• ensure the lid is actually closed (this happens regularly)
  • ensure the FFC is connected correctly
  • ensure the cables are connected as shown in the guide
  • follow the user guide on how to set up the 00xstation system folder
You can also start the PSX with the lid opened, go into the BIOS menu and then close the lid. 
The controller inputs should become non-responsive then, as the console recognizes that there is a new disk.
If all signals are connected, the loader will then start up after a short while.