1-5 is totally normal and typical happens after an adjustments of the suspension, typically an upwards one and even if just a little. 5 is the gallery depressing after filling the reservoir. During some movements, you may hear the same "compressor fart" before it starts up. It must. The compressor can not start if the gallery is under pressure, the piston can not move.

6 is odd because if the reservoir opens the gallery pressure should in turn shoot up. That would imply that the center valve block is leaking OR the reservoir itself has a leak. Which is fairly common because of rust. Normally if the reservoir is leaking back into the gallery you will get a code for 'gallery pressure increasing too quickly'.

Are you certain your center block is hooked up correctly? FYI - the center valve block has just that one solenoid and only opens/closes to the reservoir. It had no ability, like some think, to control front/rear strut airflow. It is wide open when it comes to that.

Another fact. Front and rear valve blocks can NOT be swapped around, they are specific. Yet may after market ones claim they can be used in either location. This is not true can can create a huge issues as the blocks will fail to operate correctly.

Your last sentence, spot on.

A basic small "upwards" adjustment loos like this:

EAS says a strut or more need to go up.
Gallery pressure is read, if over a certain value you will hear a compressor fart.
Compressor energizes.
A small delay before ANY valve block opens - this is to get the gallery pressure up to something reasonable (150psi?) instead of the vehicle dropping slightly as a valve block opens into an empty gallery.
Typically rear valve block opens first.
Then front valve block. If the change is small, the rear will close up before the front opens. If there is a major change, you may get a seesaw action between front and rear. Basically the EAS hates to lift all four corners at once, but it will.
Once height is reached front/rear blocks will close up if needed.
At this point, you may actually hear the compressor turn off and fart.
Compressor will start back up, if it farted, or continue to run but now with the center block open to reservoir.
Once target PSI is reached, center block will close.
Compressor turns off and usually farts.

At that point your reservoir should hold pressure but your gallery, which is the ONLY pressure observed, will bleed off and can drop to zero eventually. So if you are seeing very little pressure after a cycle like that when the center block opens, money is a on a leak at the center block, line or reservoir itself. if you have an 05/06 and maybe on some 07 models you can actually fit a pressure gauge to the front of the tank by removing a plug.

 

Oh, diagram of center block.

 

Gonna double check my hose routing. The bends make it pretty easy to tell what pipe is suppose to go where, but I may have swapped something over somewhere.

I definitely didn't think about the wiring being different between front and rear, but it makes sense that they may be mirrored in wiring and hose routing. Seems silly that they made two distinct parts for something that basically functions exactly the same front to rear axle.

But that should only effect the individual struts in the rear, correct? It shouldn't change the solenoids being normally closed until they see 12 volts. Maybe I've made too many changes and I should go back to all the old blocks.

Too bad the rear block is such a pain to get to. I think I'll drop the spare tire to get to it this time, I'm not sure I've got the patience to do it from the wheel side again.

Edit to add: saw your post in another thread with the correct part numbers for front and rear so that will help me sort my pile of parts again

 

If you get the blocks mixed up what happens is the EAS will say - hey, lets drop the rear right. Instead the rear left does. And then faults, eventually OR often times assumes you are stuck on something and will suddenly go into extended mode.

 

Welp. Guess who had the rear axle line hooked into the reservoir valve? And my brain got stuck on other high level issues when it was such a rookie mistake.

I appreciate you helping me sort this. Because of your advice I'll be able to correct the rear valve block before it gives me a fault.

 

Ah! Well that explains A LOT. Sometimes it is the simple stuff.