Yup, you're looking for solid red at highway mode after it's done with checks and then when it goes from blink to solid ready...HONK! It never fails either that or the expello gets me when I'm under the truck or not expecting it. Glen (who posted above) has had several of these trucks and is a smart experienced dude and he's in the Springs. That PDF is actually a pretty good source of info in one spot, besides finding all the pieces all over in the TM's. I think we're both CTIS fans and have troubleshot some sort of issue. Once you get the list done, make sure you either have CTIS on and working or disconnected if you think there is a problem. A faulty CTIS can be frustrating to come and find all the tires flat. Leaks is the main culprit in that system, but sometimes components fail. CTIS can overcome some tire leak issues but air leaks should be near the top of the list of fixes. In the tire area, CTIS can help be the indicator to finding some of them. Brakes being the higher priority issue related to air IMO.
Your truck looked pretty complete from the pics, anything missing?