Boost Pressure Gauge
WARNING: This page is about a different car, the 2020 Ford F-550 Super Duty, 2020 Ford F-450 Super Duty, 2020 Ford F-350 Super Duty, 2020 Ford F-250 Super Duty, and 2020 Ford F-150. 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.