Starting System
WARNING: This page is about a different car, the 2014 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.
The starting system controls the cranking of the engine. The starter motor is enabled by the starter relay when the relay is activated by the PCM . The PCM receives inputs from the ignition switch, TCM and the BCM before activating the starter relay to initiate cranking of the engine.