Thanks for this info.
There are a couple of possible issues. One you have a valve block that distributes the air to the corners that are needed so if the vehicle is not reaching the proper ride height, then that is one of two main reasons. First it is either a mechanical problem that it cannot reach the height.
This would be a pump not being able to supply the pressure or a leak that is preventing the height from being reached.
Otherwise, we have an electrical issue that is making the module think it is not getting to the proper height.
So, it sounds like you have an actual issue getting to the proper ride height and with the codes that you have, the leak is in the pump and reservoir side of the system.
Once the system is filled the lines are sealed off and if they are holding their height then you have no leak in that side.
Basically, it looks like the pump is not able to fill the system to the needed amount or there is a leak between the pump and reservoir that is causing the pump to not fill the system properly.
This would explain the different noise the pump is making. What I would do is replace the pump and valve block and retest this.
It appears you can get a pump assembly and valve block for a reasonable price.
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Thursday, June 9th, 2022 AT 11:00 AM