Circuit Description
WARNING: This page is about a different car, the 2010 Suzuki Kizashi. However, it is still accessible from the selected car via links, so may be relevant.
When push engine switch to change ignition mode to "ON", the main relay turns ON (the contact point closes) and the main power is supplied to ECM. And then ECM supplies 5 V power to each sensor (A/C refrigerant pressure sensor, EVAP leak check pressure sensor, APP sensor and TP sensor).