PXI Signal Insertion Switch Modules, also known as fault insertion units (FIUs), provide a set of feedthrough channels, which make the switch transparent to the system when closed. You can open or short these channels to one of two fault buses, allowing you to simulate open or interrupted connections as well as shorts between pins, shorts to battery voltages, and shorts to ground on a per-channel basis. When controlled with the LabVIEW Real-Time Module, the PXI Signal Insertion Switch Module can validate the integrity of control systems including engine control units (ECUs) and full authority digital engine controls (FADECs). You can also use the FIU models for hardware-in-the-loop (HIL) applications and electronic reliability tests.