Pump pressure is constant up to the control valve. When a function is called for the dump valve closes and diverts the fluid to the valve spools instead of dumping back to tank. The sensors on the control valve signal the ecu to turn off the dump valve and enable the flow through valve normally and as you pull the lever it sends fluid to whichever function you are calling for. At the same time it signals the throttle control to rev up the engine.
If there are any faults detected it disables everything and should signal the ecu to display a fault code associated to the type of fault and component detected. Display a mil light or display a code with associated symbol.
If there are no codes displayed at all then it may not be seeing any input signal. So yes it might be a high possibility the sensor on the levers are not picking up lever movement.
One other thing is i would check and make sure there are no fuses blown and check connectors in that circuit.