2004 X5 3.0D Self level been on diagnostic help?

[Bentedder]

I have been having trouble with the air suspension on my car its has the 4 air bag system. Recently the fault appeared on the dashboard with "SELF LEVEL INACTIVE" So i purchased some INPA software a while ago for my old e46. But decided to plug in my x5 an the following faults appeared on the suspension menu of inpa system:

116 Reservoir Pressure Remains constant, When filling of reservoir is requested.
58 CAN Bus

These are the 2 fault codes an explaination with them. Anyone know what could be wrong with the suspension?
I cleared the fault codes and while on the drive i used the hand controller to lower the suspension it went down. Then bring it back up to level and it Rose. So i dont really know what is wrong?
If i leave the car a few days the car does lower. Has anyone had this fault before? Someone on another forum told me to open the boot/trunk while the vehicle has been parked to see if the compressor would kick in an it did it returned the ride height to normal. I am suspecting a faulty relay or sensor?
But any help would be great as im not a suspension or X5 expert.