If car one wheel is not going down, others are not going up in height is malfunctioned sensor the one that stays up?

Is it easy to change? Couldn´t find any threads related to sensor sub-assy.
I have sensor that susposed to work. Question is which one to swap and where to find it?

2001.

 

Found this one, will give it a try.

 

Working part





Old part






Part removed





Height before, button did not do anything








Height after



New part applied

 

Car is in rough shape ?

 

Just winter, wet and dirty. Awesome car. Don't ever want to sell