Starting Mode

When the ignition is first turned ON, the ECM supplies voltage to the FPCM for 2 seconds. While this voltage is being received, the FPCM closes the ground switch of the fuel pump, and also supplies a varying voltage to the fuel tank fuel pump module in order to maintain the desired fuel rail pressure. The ECM calculates the air/fuel ratio based on inputs from the engine coolant temperature (ECT), mass air flow (MAF), manifold absolute pressure (MAP), and throttle position (TP) sensors. The system stays in starting mode until the engine speed reaches a predetermined RPM.