Cummins ISX Turbo Air Control Valve

Hello

I have 05 Volvo with Cummins in it and I just noticed I am not getting enough boost and I had a mechanic hook up computer and he says I am getting about 23k psi when I should have 70k. He says turbo actuator is not opening and closing turbo at all. He says turbo air control valve should send air to actuator but when I inspect turbo air control valve there is only electrical plug on it and one air line going to turbo, so how can this valve send air to actuator if it's not getting air from the truck, has anyone been dealing with something like this please any help would be very much appreciated

 

This is a CM870, Cummins changed in 2005 how this Turbo Air Control Valve works, my Engine number falls under new system, lt used to be air coming from tank to filter to valve to actuator. Now it doesnt have filter and air control valve is different. But I guess I still need air from truck to valve so this valve can push the air to turbo actuator. I think now the air is supposed to come from air dryer to this valve and then even ecm tells valve when to open up so the air can go to turbo actuator

 

I think it should have close to 70 that's at least what the guy at dealership said when I took my truck and my truck is also CM870

 

Anyone out there with this engine willing to take a picture of turbo air control valve, (see pic attached)just to confirm there is a air connected on the bottom port of the valve and where is this air line connected to, mine doesn't have air connected on the bottom port