Apparatus, systems, and methods for identifying a fault in an electronic system are provided. One apparatus includes memory storing a model of the electronic system, a processor, and a fault module. The processor is configured to pass system inputs through the model to generate corresponding simulated outputs, and the fault module is configured to determine the fault based on a comparison of the system outputs and the simulated outputs. A system includes an electronic system including multiple components generating system outputs based on system inputs and the apparatus for identifying a fault in the electronic system discussed above. One method includes generating a model of the electronic system, passing one or more inputs to the electronic system through the model to generate corresponding simulated outputs, and determining the fault based on a comparison of the one or more simulated outputs and one or more electronic system outputs.