It is your air shocks/struts (they are the same). It is you air shocks on the front giving you the symptom of a fault shock or in ability to maintain height with proper air pressure, or it is a system diagnosis causing you to get a fault system malfunction reading,and because of the inability to maintaining proper height the shock fails, it has something to do with "air supply" or the ability to maintain or hold the air the shock receives from the air system.
There are a few places to look. Since it is the front, this symptom can be caused by air leak in the lines to the front air shock(s), a weak air compressor in trunk (long shot), or air lines to the compressor being damaged (also in trunk under tire, and under the car carriage), or failure to the part that directs and maintain the air pressure to all 4 tires air shocks. Yes, and it could be the actual air shock failing. Usually the failure start with the car sitting, and rising to the proper height when the car is started. This is usually leak in the air shock with failure eminent. If the car no longer rises when started after about 5 minutes and both shocks (front or back) are low then look for line leak or failure in parts related to the system. If it is only one side then look at the air shock.
In the winter the air shocks are subject to slight decreased height because cold air is more compressed, and the compressor correct the height when you start the car. However, this winter height difference is usually not detectable to the eye, however when it is detectable there is usually a leak. Also, the amount of air is usually close to the normal PSI when warm. It is like your tires having a lower PSI when cold and expanding when driven, with this slight change in PSI on cold starts, also not detectable to the eye.
If both air shock are low, then I would check lines, because both front or back air shocks do not usually fail together. If one side is low, I would check the air shock itself. The shock (new) will stress your wallet for about $800 each. You can get rebuilt ones for about $400 (more or less) with core exchange. I would not buy a used (not rebuilt) one because the life of the air shocks are about 100,000 miles, as the seals begin to fail, and you will not usually know if the miles indicated on that shock is true. Because of this unknown and the fact that that non-rebuilt shock may be on it last days also, It is best to get a rebuilt one, or new one.
Since you did not indicate that it was one side or the other and, if the conditions shows that the front is low and never raises, I would say their is a problem with the air pressure system getting air to those shocks, and feel safe that it is not the shocks themselves. This would also give you the "AIR SUSPENSION FAULTY" light. Could be wrong but start there, then work your way to the shocks. Hope this helps.
