S Connector Circuit Check [QR25DE]: Description
WARNING: This page is about a different car, the 2011 Suzuki Equator. However, it is still accessible from the selected car via links, so may be relevant.
Terminal "1" (S) is the power supply for the starter motor magnetic switch. Terminal 1 is supplied with power when the ignition switch is turned to the START position while the selector lever is in the P or N position.