The ECM determines the battery power according to the voltage of the BATT terminal while the engine is running (not cranking).  

The battery current sensor installed on the positive (+) battery terminal detects the amount of current supplied from the generator. The battery current sensor changes current to voltage (at the positive (+) battery terminal) and sends it to the ECM.

The high pressure side fuel pump is attached to the insulator, which is attached to the cylinder head cover. The pump activates according to the position of the cam on the exhaust side camshaft (right bank).

When the Intake Air Control Valve (IACV) opens and closes, the ACIS control circuit causes the engine load intake efficiency to increase. When the engine is running at 2,450 to 4,100 rpm and the throttle valve opening angle is 30°or more, current flows through the ACIS control circuit and the IACV closes.

While the engine is being cranked, the positive battery voltage is applied to terminal STA of the ECM. If the ECM detects the Starter Control (STA) signal while the vehicle is being driven, it determines that that there is a malfunction in the STA circuit. The ECM then illuminates the MIL and sets the DTC.

The ECM continuously monitors its internal memory status, internal circuits, and output signals sent to the throttle actuator. This self-check insures that the ECM is functioning properly. If any malfunction is detected, the ECM will set the appropriate DTC and illuminate the MIL.

The battery supplies electricity to the ECM even when the engine switch is in the off position. This power allows the ECM to store data such as DTC history, freeze frame data and fuel trim values. If the battery voltage falls below a minimum level, these memories are cleared and the ECM determines that there is a malfunction in the power supply circuit.

The battery thermometer sensor installed on the battery cover detects battery temperature. A thermistor is integrated into the battery thermometer sensor, and the resistance in the battery thermometer sensor changes according to the battery temperature. The resistance of the thermistor in the battery thermometer sensor decreases as the battery temperature increases. The resistance increases as the temperature decreases.

The idle speed is controlled by the Electronic Throttle Control System (ETCS). The ETCS is comprised of: 1) a one valve type throttle body; 2) the throttle actuator, which operates the throttle valve; 3) the throttle position sensor, which detects the opening angle of the throttle valve;

The stop light switch is a duplex system that transmits two signals: STP and ST1-. These two signals are used by the ECM to monitor whether or not the brake system is working properly. If the signals, which indicate the brake pedal is being depressed and released, are detected simultaneously, the ECM interprets this as a malfunction in the stop light switch and sets the DTC.