No 4x4...what am I missing

[Truck3]

When activating the ESOF (Electronic shift on the fly) from 2H to 4H, I get a dash indicator stating it is in 4X4, but it is not.
Did the vacuum test by placing the heat controls on vent with the fan on high, and then switching to 4H. There was no change to the default defrost mode. Therefore, I can rule out the PVH (pulse vacuum hub lock)????
I think the electrical relay for the hub lock in in the right kick panel, as I can hear it click when the ESOF switch is made.
What am I missing here?
No 4X4.
2007 Expedition EL 5.4 L

Any help would be greatly appreciated as we got 6" of snow last night and I have no traction.

 

[stamp11127]

First step is check fuses for the 4wd circuit. The relay is protected by a minimum of 2 fuses.

 

[Truck3]

I checked all fuses, they are good. Could replacement hubs not being compatible be an issue? Had the hubs replaced with Timken after one began to go. Never had to use 4x4 since then.
I'm leaning toward the PVH but I am unable to locate it in order to rule it out. Any ideas?

 

[46L281GT]

With the hubs replaced it could be that a vacuum line wasn't reconnected when the new ones where installed.

 

[Truck3]

checked the lines and all appear to be in tact. Nothing visual so far. Even following those lines back from the hub, I am unable to locate the PVH.