It is common to create a motion simulation file in Simcenter 3D based on an existing part file. This will set the part file as the CAD source (formerly called master) part of motion simulation file. The motion model is tied to this part file and will use this as the reference for all of the CAD. An issue occurs when a motion simulation is referencing the wrong instance of a part file. This means that the CAD source part can be in a different folder and won’t reflect any changes made to a similar part of the same name in the correct folder. This article will walk through how to change the CAD source part using the Replace Component command.