Boost Pressure Gauge
WARNING: This page is about a different car, the 2013 Ford F-550 Super Duty, 2013 Ford F-450 Super Duty, 2013 Ford F-350 Super Duty, and 2013 Ford F-250 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.
The boost pressure gauge is controlled by the instrument panel cluster. The PCM sends a message through the controller area network (CAN) to the instrument panel cluster indicating engine boost pressure.