The dash uses the FORD SCP J1850 Data bus to move data around the
car. This is used by everything from ECU, ABS, Radio, Dash, lighting etc...

For example, On the ST (sure its the same for the FRS),

The wheel sensors used on the abs, feed infor to the abs ecu,
data is then sent out on the data bus (after the dash unit requests it)
to get the road speed for the dash and the traction control systems.

Only one sensor feeds multiple systems to save money and less parts
to go wrong.

So there will be ONLY one pressure sensor for the ecu of which the dash
displays the available data. Not sure what the value you say (222)
represents though. Probally 2.22 kpa (kilo pascals absolute).

Dont know what standard boost the FRS runs but after removing the
absolute atmospere pressure......
1.2 bar boost ???
(possibly showing half kpa in which case its 0.6 bar boost) ????????

Even if this is wrong the data will be consistent.
I.E. If your cars boost shows 222 on standard map and the same on
remapped then you have a problem as clearly the boost hasnt risen
for what ever reason.