A quick recap to catch up since this is so old.
The Close out over my stairs would not close and I started trying to find out why about 6 weeks ago. It was initially suggested to be the air control valve, so when I saw a NOS one listed reasonably I bought it. Put it on and it still didn't fix things.
Next I found a serious leak in the end seal of the Bimba Air cylinder. Ordered an new one and waited about a month while it was made. Put it in and had no leaks in the air cylinder, but it still did not fix it. Then I found a very minor leak on the bottom of one of the Bimba air fittings (FCP2K).
I bought two of them locally and replaced both. Aired the coach up and no leaks, but still not fixed!
Then I took a small screwdriver and put it into the red slot on the side (see picture) and turned it counter clockwise until it stopped. I could hear the air escaping and then the air valve switching. The close out then extended to the closed position. Turn it clockwise and the close out retracted to the open position. This tells me that pneumatically the system is working.
So now I am thinking that this is electrical, or more specifically a grounding issue. l am getting 14.4 volts to the top front spade terminal on the solenoid looking box with the close out switches in one of their positions and no volts with the switches in the other. This is from the front spade terminal to the heavy negative ground stud at the front of the coach. I believe that the air control valve defaults to the close out open position by a spring inside the valve that has to be overcome by air pressure which only happens when 12 volts is applied and air diverted internally.
Now I want to try to test this out by jumpering a ground to the solenoid on top of the air control valve. The problem is I am not sure which of the other two terminal connectors are grounds. The top back terminal has 2 black wires going to it, but they disappear into a closed harness. The bottom horizontal one has a single black wire going to it and also disappears into a closed harness.
Does anyone know which is the ground, or where the grounds terminate? Does anyone have another direction to go in. I think I have pretty much replaced most of the system, but that is ok with me since parts of it were pretty much worn out.
Thanks for any help, I am not giving up, but this one is making me work for it!