Although the LP Fuel Pump does prime for 2-seconds, I highly doubt you hear it, the noise you are hearing is the - Waste Gate Actuator, running a self test cycle (part of the PCM Wake circuit)
You can watch it cycle by looking through the RF wheel well when the door is opened.
WARNING - When the Ford Pass checks in and wants a Health / Location update that actuator will cycle, so when you are working under the truck and it cycles - the very first time it happens to you - Lets just say, you will find out how fast you can move when you are on your back