How do I know if the suspension control module is bad in a 2005 lincoln navigator?

Why have a navigator if you don't have air suspension everyone who wants you to switch the coilovers either sells coilovers or maybe they're just too lazy or not smart enough to deal with the air system it's not that complicated the solenoids are on the bags the pump runs when the sensors work the sensors are cheap on eBay and there is a air control module behind the front bumper on the passenger side that goes bad not that expensive or hard to change hook power up to your pump if it turns on its not your pump if your sensors look bad just buy new ones they're not expensive that leaves the module change the module Why have a navigator if you don't have air suspension everyone who wants you to switch the coilovers either sells coilovers or maybe they're just too lazy or not smart enough to deal with the air system it's not that complicated the solenoids are on the bags the pump runs when the sensors work the sensors are cheap on eBay and there is a air control module behind the front bumper on the passenger side that goes bad not that expensive or hard to change hook power up to your pump if it turns on its not your pump if your sensors look bad just buy new ones they're not expensive that leaves the module change the module