My system is not leaking but won't pump up even put air from air compressor in on 1994 Lincoln Continental

Tried to put air in manually from my compressor it still did not move at all is there a sylenoid that would stop all four wheels from going up ? It holds pressure when I take it apart it releases

Asked by for the 1994 Lincoln Continental
yes, there is a solenoid
Other than on each wheel
you also have a check valve...that pumps to each wheel....possibly it is stuck
Where is the check valve on this car