SFI SYSTEM

FUNCTION OF MAIN COMPONENTS

1. The main components of the engine control system are as follows:

   Component		Outline	Quantity	Function
   ECM		32-bit CPU	1	Optimally controls the engine control system to suit the operating conditions of the engine in accordance with the signals provided by the sensors.
   Air Fuel Ratio Sensor		Heated Type (Planar Type)	2 (1 each bank)	Detects the oxygen concentration in the exhaust gas by measuring the electromotive force which is generated in the sensor itself.
   Heated Oxygen Sensor		Heated Type (Cup Type)	2 (1 each bank)
   Mass Air Flow Meter Sub-assembly	Air Flow Meter	Silicon Chip Type	1	Uses a built-in silicon chip to directly detect the intake air mass.
   	Intake Air Temperature Sensor	Thermistor Type	1	Detects the intake air temperature.
   Engine Coolant Temperature Sensor		Thermistor Type	1	Detects the engine coolant temperature.
   Fuel Pressure Sensor	For Low Pressure	Semiconductor Type	1	Detects the fuel pressure in the fuel delivery pipe sub-assembly.
   	For High Pressure	Semiconductor Type	1
   Crank Position Sensor [No. of Rotor Teeth]		Magnetic Resistance Element (MRE) Type [36 - 2]	1	Detects the engine speed and performs cylinder identification.
   Cam Position Sensor (No. 2 Crank Position Sensor) (Intake) [No. of Rotor Teeth]		Magnetic Resistance Element (MRE) Type [3]	2 (1 each bank)	This sensor performs cylinder identification. This sensor is used to detect the intake camshaft position.
   Cam Position Sensor (No. 2 Crank Position Sensor) (Exhaust) [No. of Rotor Teeth]		Magnetic Resistance Element (MRE) Type [3]	2 (1 each bank)	This sensor performs cylinder identification. This sensor is used to detect the exhaust camshaft position.
   Throttle Body with Motor Assembly	Throttle Position Sensor	Non-contact Type	1	Detects the throttle valve opening angle.
   	Throttle Control Motor	DC Motor	1	Regulates the opening of the throttle valve in accordance with the signals from the ECM.
   Accelerator Pedal Sensor Assembly		Non-contact Type	1	Detects the amount of pedal effort applied to the accelerator pedal.
   Knock Control Sensor		Built-in Piezoelectric Element Type (Flat Type)	2 (1 each bank)	Detects engine knocking indirectly through the vibration of the cylinder block caused by engine knocking.
   Cam Timing Oil Control Solenoid Assembly		Solenoid Type	4	Changes the oil passage to the VVT-i or VVT-iW controller in response to signals from the ECM.
   Fuel Injector Assembly	For Port Injection	12-hole Type	6	This injector is an electromagnetically-operated nozzle which injects fuel in accordance with signals from the ECM.
   	For Direct Injection	High Pressure Single Slit Nozzle Type	6	This injector contains a high-pressure electromagnetically-operated nozzle used to inject fuel directly into the cylinder.
   Ignition Coil Assembly		Type with Igniter	6	Incorporates an igniter and provides the high voltage electricity necessary for ignition in accordance with signals from the ECM.
   Spark Plug		Iridium-tipped Type	6	Produces a spark inside the cylinder using high voltage electricity delivered from the ignition coil assembly

SYSTEM CONTROL

1. The engine control system has the following features:

   System	Outline
   Direct Injection 4-stroke Gasoline Engine Superior Version Sequential Multiport Fuel Injection (D-4S SFI) System	This is an L-type SFI system. It directly detects the intake air volume with a hot-wire type mass air flow meter sub-assembly. The D-4S SFI system is a fuel injection system which combines direct injection injectors and port injection injectors. Based on signals from each sensor, the ECM controls the injection volume and timing of each type of injector (direct and port injection types) in accordance with the engine speed and engine load in order to optimize combustion conditions.
   Electronic Spark Advance (ESA)	Ignition timing is determined by the ECM based on signals from various sensors. The ECM corrects ignition timing in response to engine knocking. This system determines the optimal ignition timing in accordance with the signals received from the sensors and sends ignition (IGT) signals to the igniters.
   Electronic Throttle Control System-intelligent (ETCS-i)	Optimally controls the opening angle of the throttle valve in accordance with the accelerator pedal input and the engine and vehicle operating conditions.
   Variable Valve Timing-intelligent Wide (VVT-iW)	Regulates operation of the intake camshaft to ensure optimal valve timing in accordance with the engine operating conditions.
   Variable Valve Timing-intelligent (VVT-i)	Regulates operation of the exhaust camshaft to ensure optimal valve timing in accordance with the engine operating conditions.
   Acoustic Control Induction System (ACIS)	Switches the intake air passages based on engine speed and throttle valve opening angle to provide high performance in all engine speed ranges.
   Cooling Fan Control	The cooling fan ECU steplessly controls the speed of the fans in accordance with the engine coolant temperature, vehicle speed, engine speed, and air conditioning operating conditions. As a result, the cooling performance is improved.
   Fuel Pump Control (for Low Pressure)	Based on signals from the ECM, the fuel pump control ECU assembly controls the fuel pump. The fuel pump is stopped when any of the Supplemental Restraint System (SRS) airbags is deployed in a collision.
   Variable Fuel Pressure Control	Controls the fuel pressure (low pressure) by controlling the fuel pump (for low pressure) speed in accordance with the engine condition.
   Fuel Pump Control (for High Pressure)	Regulates the fuel pressure within a range of 2.0 to 20 MPa in accordance with driving conditions.
   Air Fuel Ratio Sensor and Heated Oxygen Sensor Heater Control	Maintains the temperature of the air fuel ratio sensor and heated oxygen sensor at an appropriate level to increase the ability of each sensor to accurately detect the oxygen concentration in the exhaust gas.
   Cranking Hold Function (Starter Control)	Once the engine switch is pushed, this control operates the starter until the engine starts.
   Brake Override System	The driving torque is restricted when both the accelerator and brake pedals are depressed. (For the Activation Conditions and Inspection Method, refer to the repair manual)
   Drive Start Control	If an abnormal shift (R to D/M, D/M to R, N to R, P to D/M, P to R) is detected while accelerating, a warning is displayed in the combination meter assembly and driving force is reduced to limit the acceleration, helping to avoid a collision.
   Thermostat Heater Control	Ensures improved fuel economy by heating the heater inside the thermostat and reducing the friction according to the engine condition.
   Evaporative Emission Control	The ECM controls the purge flow of evaporative emissions (HC) from the canister in accordance with the engine operating conditions.
   Engine Immobiliser	Prohibits fuel delivery and ignition if an attempt is made to start the engine with an invalid key.

FAIL-SAFE

1. When a malfunction of any of the sensors is detected, there is a possibility of an engine or other malfunction occurring if the ECM were to continue normal control. To prevent such a problem, the fail-safe function of the ECM either relies on the data stored in memory to allow the engine control system to continue operating, or stops the engine if a hazard is anticipated. For details, refer to the Repair Manual.

DIAGNOSIS

1. When the ECM detects a malfunction, the ECM records information related to the fault. Furthermore, the Malfunction Indicator Lamp (MIL) in the combination meter assembly illuminates or blinks to inform the driver.

2. The ECM also stores Diagnostic Trouble Codes (DTCs) for malfunctions it has detected. The DTCs can be accessed by using the Global TechStream (GTS).

3. For details, refer to the Repair Manual.