The EM-250, Manual Fault Box for ECM/PCM, is a device that allows the instructor to manually enable failure or malfunction of engine sensors and actuators through switches. The fault insertion module comes with two fifteen-pin connectors (male and female) that are located on right side of the box.

The EM-250 module is used to intercept data link communication between the PCM and the engine operating parts, and can be installed on all the Consulab engine trainers. If the faults are disabled, the fault insertion module will not affect normal operation of the engine.