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EG-44 – 2ZR-FE ENGINE

6. ETCS-i (Electronic Control System-intelligent)

General D The ETCS-i is used, providing excellent throttle control in all the operating ranges. D The accelerator cable has been discontinued, and an accelerator pedal position sensor has been provided on the accelerator pedal. D In the conventional throttle body, the throttle valve opening angle is determined invariably by the amount of the accelerator pedal effort. In contrast, the ETCS-i uses the ECM to calculate the optimal throttle valve opening angle that is appropriate for the respective driving condition and uses a throttle control motor to control the opening angle. D The ETCS-i controls the ISC (Idle Speed Control) system, the TRAC (Traction Control), VSC (Vehicle Stability Control) system and cruise control system*. D In case of an abnormal condition, this system switches to the limp mode.

" System Diagram A

Throttle Valve Accelerator Pedal Position Sensor

Throttle Control Motor

Mass Air Flow Meter

Ignition Coil Cruise Control ECM Switch*

Fuel Injector

Skid Control ECU

CAN (V Bus) 01ZEG05Y

*: Models with Cruise Control System ENGINE – 2ZR-FE ENGINE EG-45

Construction

Throttle Body

Throttle Position Sensor Portion Reduction Gears

A

Throttle Control View from A Motor Magnetic Yoke

Hall IC (for Throttle Position Sensor)

Throttle Valve Throttle Control Motor

Cross Section 00REG05Y

1) Throttle Position Sensor The throttle position sensor is mounted on the throttle body to detect the opening angle of the throttle valve.

2) Throttle Control Motor A DC motor with excellent response and minimal power consumption is used for the throttle control motor. The ECM performs the duty cycle control of the direction and the amperage of the current that flows to the throttle control motor in order to regulate the opening angle of the throttle valve.

Operation

1) General The ECM drives the throttle control motor by determining the target throttle valve opening angle in accordance with the respective operating condition. D Non-linear Control D Idle Speed Control D TRAC Throttle Control D VSC Coordination Control D Cruise Control* *: Models with Cruise Control System EG-46 ENGINE – 2ZR-FE ENGINE

2) Non-linear Control The ECM controls the throttle valve to an optimal opening angle that is appropriate for the driving condition such as the amount of the accelerator pedal effort and the engine speed in order to realize excellent throttle control and comfort in all operating ranges.

" Control Examples During Acceleration and Deceleration A

: With Control : Without Control " Vehicle’s Longitudinal G 0

" Throttle Valve Opening Angle 0 " Accelerator Pedal Depressed Angle 0 Time ! 005EG13Y

3) Idle Speed Control The ECM controls the throttle valve in order to constantly maintain an ideal idle speed.

4) TRAC Throttle Control As part of TRAC system, the throttle valve is closed by a request signal from the skid control ECU if an excessive amount of slippage is created at a driving wheel, thus it facilitates the vehicle in ensuring stability and driving force.

5) VSC Coordination Control In order to bring the effectiveness of the VSC system control into full play, the throttle valve opening angle is controlled by effecting a coordination control with the skid control ECU.

6) Cruise Control* An ECM with an integrated cruise control ECU directly actuates the throttle valve for operation of the cruise control. *: Models with Cruise Control System ENGINE – 2ZR-FE ENGINE EG-47

Fail-safe of Accelerator Pedal Position Sensor

D The accelerator pedal position sensor is comprised of two (main, sub) sensor circuits. If a malfunction occurs in either one of the sensor circuits, the ECM detects the abnormal signal by voltage difference between these two sensor circuits and switches to the limp mode. In the limp mode, the remaining circuit is used to calculate the accelerator pedal depressed angle, in order to operate the vehicle under limp mode control.

ECM

Accelerator Pedal Position Sensor Open Main Sub Main Sub Throttle Throttle Throttle Valve Return Control Position Spring Motor Sensor

Accelerator Pedal Throttle Body 199EG45

D If both circuits have a malfunction, the ECM detects the abnormal signal by voltage from these two sensor circuits and discontinues the throttle control. At this time, the vehicle can be driven within its idling range.

ECM

Close by Accelerator Pedal Return Spring Position Sensor Main Sub Main Sub Throttle Throttle Throttle Valve Return Control Position Spring Motor Sensor

Accelerator Pedal Throttle Body 199EG46 EG-48 ENGINE – 2ZR-FE ENGINE

Fail-safe of Throttle Position Sensor

D The throttle position sensor is comprised of two (main, sub) sensor circuits. If a malfunction occurs in either one or both of the sensor circuits, the ECM detects the abnormal signal by voltage difference between these two sensor circuits, cuts off the current to the throttle control motor, and switches to the limp mode. Then, the force of the return spring causes the throttle valve to return and stay at the prescribed opening angle. At this time, the vehicle can be driven in the limp mode while the engine output is regulated through the control of the (intermittent fuel-cut) and in accordance with the accelerator opening. D The same control as above is effected if the ECM detects a malfunction in the throttle control motor system.

Fuel Injectors ECM

Accelerator Pedal Return to Position Sensor Prescribed Angle

Main Sub Main Sub Throttle Return Throttle Throttle Valve Control Spring Position Motor Sensor Accelerator Pedal Throttle Body

199EG47 ENGINE – 2ZR-FE ENGINE EG-49

7. Dual VVT-i (Variable -intelligent) System

General D The Dual VVT-i system is designed to control the and exhaust camshafts within a range of 55_ and 40_ respectively (of Angle) to provide valve timing that is optimally suited to the engine condition. This improves in all the speed ranges as well as increasing fuel economy, and reducing exhaust emissions.

Exhaust Camshaft Timing OCV* Intake Camshaft Timing OCV*

Exhaust Camshaft Position Sensor Intake Camshaft Position Sensor

ECM

Engine Coolant Temperature Crankshaft Sensor Position D Mass Air Flow Sensor Meter D Throttle Position Sensor

04FEG114Y *: Oil Control Valve

D Using the engine speed, intake air mass, throttle position and engine coolant temperature, the ECM can calculate optimal valve timing for each driving condition and controls the camshaft timing oil control valve. In addition, the ECM uses signals from the camshaft position sensor and the crankshaft position sensor to detect the actual valve timing, thus providing control to achieve the target valve timing.

ECM

Crankshaft Position Sensor Camshaft Timing Target Valve Timing Oil Control Valves Duty Cycle Mass Air Flow Meter Control Throttle Position Sensor Feedback

Engine Coolant Temp. Sensor Correction

Camshaft Position Sensors Actual Valve Timing

221EG16 Vehicle Speed Signal EG-50 ENGINE – 2ZR-FE ENGINE

Effectiveness of Dual VVT-i System

Operation State Objective Effect TDC Most Retarded

Eliminating overlap to D Stabilized idle speed During Idling EX IN reduce blow back to the D Better fuel economy intake side

BDC 281EG42

To Retarded Side Eliminating overlap to Ensured engine At Light Load reduce blow back to the EX IN stability intake side

281EG43

To Advanced Side

Increasing overlap to D Better fuel economy D At Medium Load EX IN increase internal EGR to Improved emission reduce pumping loss control

281EG44

Advancing the intake In Low to Medium valve close timing for Improved torque in low Speed Range with EX IN to medium speed range Heavy Load To Advanced improvement Side 281EG45

Retarding the intake In High Speed valve close timing for Range with Heavy EX IN Improved output volumetric efficiency Load improvement To Retarded Side 281EG46

Eliminating overlap to reduce blow back to the At Low intake side leads to the D Stabilized idle speed Temperatures EX IN lean burning condition, D Better fuel economy and stabilizes the idling

281EG42 speed at fast idle

Most Retarded D Upon Starting Eliminating overlap to D Stopping the EX IN minimize blow back to Improved startability Engine the intake side

281EG42 ENGINE – 2ZR-FE ENGINE EG-51

Construction

1) VVT-i Controller D Each controller consists of the housing driven from the timing chain and the vane coupled with the intake or exhaust camshaft. D Both the intake and exhaust sides have a four-blade vane. D The oil pressure sent from the advanced or retarded side path at the intake and exhaust camshafts causes rotation in the VVT-i controller vane circumferential direction to vary the intake and exhaust valve timing continuously. D When the engine is stopped, a lock pin locks the intake camshaft at the most retarded end and the exhaust camshaft at the most advanced end, to ensure that the engine starts properly. D An advance assist spring is provided on the exhaust side VVT-i controller. This spring applies torque in the advance direction when the engine is stopped, thus ensuring the engagement of the lock pin.

" Intake Side VVT-i Controller A

Vane (Fixed on Intake Camshaft)

Housing

Intake Camshaft

Sprocket Lock Pin

Oil Pressure

At a Stop In Operation

Lock Pin 04FEG107Y

" Exhaust Side VVT-i Controller A Sprocket Lock Pin Housing

Exhaust Camshaft

Vane (Fixed on Exhaust Camshaft)

Advance Assist Spring 04FEG108Y EG-52 ENGINE – 2ZR-FE ENGINE

2) Camshaft Timing Oil Control Valve This camshaft timing oil control valve controls the spool valve using duty cycle control from the ECM. This allows hydraulic pressure to be applied to the VVT-i controller advanced or retarded side. When the engine is stopped, the camshaft timing oil control valve (intake) will move to the most retarded position, and the camshaft timing oil control valve (exhaust) will move to the advance position.

" Intake Camshaft Timing Oil Control Valve A

To VVT-i Controller (Retarded Side) To VVT-i Controller (Advanced Side)

Spring

Sleeve Drain Drain Coil Plunger Oil Pressure Spool Valve 04FEG97Y

" Exhaust Camshaft Timing Oil Control Valve A

To VVT-i Controller To VVT-i Controller (Retarded Side) (Retarded Side)

Drain Drain

Oil Pressure 04FEG115Y ENGINE – 2ZR-FE ENGINE EG-53

Operation

1) Advance When the camshaft timing oil control valve is positioned as illustrated below by the advance signals from the ECM, the resultant oil pressure is applied to the timing advance side vane chamber to rotate the camshaft in the timing advance direction.

" Intake Side A

Vane

ECM

Rotation Direction Oil Pressure

IN Drain 04FEG109Y

" Exhaust Side A

Vane

ECM

Rotation Direction Oil Pressure

Drain IN 04FEG110Y EG-54 ENGINE – 2ZR-FE ENGINE

2) Retard When the camshaft timing oil control valve is positioned as illustrated below by the retard signals from the ECM, the resultant oil pressure is applied to the timing retard side vane chamber to rotate the camshaft in the timing retard direction.

" Intake Side A

Vane

ECM

Rotation Direction Oil Pressure

Drain IN 04FEG111Y

" Exhaust Side A

Vane

ECM

Rotation Direction Oil Pressure

IN Drain 04FEG167Y

3) Hold After reaching the target timing, the valve timing is held by keeping the camshaft timing oil control valve in the neutral position unless the traveling state changes. This adjusts the valve timing at the desired target position and prevents the engine oil from running out when it is unnecessary. ENGINE – 2ZR-FE ENGINE EG-55

8. Control A fuel cut control is used to stop the fuel pump when the is deployed in the front or side collision. In this system, the airbag deployment signal from the airbag sensor assembly is detected by the ECM, and it turns OFF the circuit opening relay. After the fuel cut control has been activated, turning the ignition switch from OFF to ON cancels the fuel cut control, and the engine can be restarted.

From Battery

Circuit Opening Front Airbag Airbag Relay Sensors Sensor ECM (RH and LH) Assembly

CAN (V Bus) Fuel Pump Motor Curtain Shield Side Airbag Airbag Sensor Sensor Assembly Assembly (RH and LH)* (RH and LH)*

04FEG24Y

*: Models with Side and Curtain Shield