1997 Lincoln Continental Rear Raises Way Until Too Stiff Drive Won T Lower

The rear raises all the way up, (until too stiff to drive) and won't lower back down except when doing it manually by turning spring selenoid's to completey release air. Need to know if it's more likely the spring selenoid or one of the rear ride height sensors. I read through a similar question you previously answered, and you said that the Continental and towncar use the same system. Is the control module behind the glovebox, and the Diagnostic plug: right side of trunk behind trim panel, being a 1997 continental not a towncar? thank you