Page 30 of 2000
ENGINE - 2AZ-FE ENGINE
01MEG05Y
DEFGGER SWITCH
TA I L L I G H T S W I T C H
STOP LIGHT SWITCH
CURRENT SENSOR
CANISTER PUMP MODULE
CANISTER PRESSURE
SENSOR
TRANSPONDER KEY ECU*
AIRBAG SENSOR ASSEMBLY
EPS ECU
AIR CONDITIONING ECU
SKID CONTROL ECU
DLC3
BATTERYELS1
ELS3
STP
ST1-
THB
VCIB
PPMP
IMI
IMO
CANH,
CANL
TC
TA C H
BATTECMFA N H
FA N L
MPMP
VPMP
PRG
RLO
DF
MREL
+B
WCOOLING FAN CONTROL
COOLING FAN RELAY No.1
COOLING FAN RELAY No.2
COOLING FAN RELAY No.3
EVAPORATIVE EMISSION
CONTROL
CANISTER PUMP MODULE
LEAK DETECTION PUMP
VENT VALVE
GENERATOR
MAIN RELAY
COMBINATION METER
MIL
PURGE VSV
: CANEG-33
*: Models with Engine Immobilizer System
Page 35 of 2000

ENGINE - 2AZ-FE ENGINE
271EG45
Alumina
Dilation Layer
Alumina
Platinum
Electrode
Sensor Element (Zirconia)Heater AtmospherePlatinum
ElectrodeHeater
Atmosphere
Sensor Element
(Zirconia)
Planar Type Air-fuel Ratio Sensor Cup Type Heated Oxygen Sensor
204EG54
Temperature Sensing
Element
Platinum Hot-wire
ElementAir FlowIntake Air
Temperature
Sensor EG-38
2) Construction
The basic construction of the air-fuel ratio sensor and heated oxygen sensor is the same. However, they
are divided into the cup type and the planar type, according to the different types of heater construction
that are used.
The cup type sensor contains a sensor element that surrounds a heater.
The planar type sensor uses alumina, which excels in heat conductivity and insulation, to integrate a
sensor element with a heater, thus realizing the excellent warm-up performance of the sensor.
Warm-up Specification
Sensor TypePlanar TypeCup Type
Warm-up TimeApprox. 10 sec.Approx. 30 sec.
Mass Air Flow Meter
The compact and lightweight mass air flow meter, which is a plug-in type, allows a portion of the intake
air to flow through the detection area. By directly measuring the mass and the flow rate of the intake air,
the detection precision is ensured and the intake air resistance is reduced.
This mass air flow meter has a built-in intake air temperature sensor.
Page 40 of 2000

ENGINE - 2AZ-FE ENGINE
00REG17Y
Accelerator Pedal
Position SensorThrottle Valve
Throttle Position SensorThrottle
Control
Motor
Mass Air
Flow MeterECMSkid
Control
ECU
Ignition
CoilFuel
Injector
: CANEG-43
6. ETCS-i (Electronic Throttle Control System-intelligent)
General
The ETCS-i is used, providing excellent throttle control in all the operating ranges. In the 2AZ-FE
engine, the accelerator cable has been discontinued, and an accelerator pedal position sensor has been
provided on the accelerator pedal.
In the conventional throttle body, the throttle valve opening is determined by the amount of the
accelerator pedal effort. In contrast, the ETCS-i uses the ECM to calculate the optimal throttle valve
opening that is appropriate for the respective driving condition and uses a throttle control motor to control
the opening.
The ETCS-i controls the IAC (Idle Air Control) system, the TRAC (Traction Control), VSC (Vehicle
Stability Control) system and curise control system.
In case of an abnormal condition, this system switches to the limp mode.
System Diagram
Page 42 of 2000

ENGINE - 2AZ-FE ENGINE
005EG13Y
: With Control
: Without Control
Vehicle’s
Longitudinal G
Throttle Valve
Opening Angle
Accelerator Pedal
Depressed Angle
0
0
0
Time
EG-45
2) Normal Throttle Control (Non-linear Control)
It controls the throttle to an optimal throttle valve opening 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
3) Idle Air Control
The ECM controls the throttle valve in order to constantly maintain an ideal idle speed.
4) TRAC Throttle Control
As part of the TRAC system, the throttle valve is closed by a demand signal from the skid control ECU
if an excessive amount of slippage is created at a driving wheel, thus facilitating the vehicle in providing
excellent 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.
Page 49 of 2000

ENGINE - 2AZ-FE ENGINE
01NEG09Y
01NEG10Y
Air
Conditioning
ECU
Engine Coolant
Temperature SensorFANL
ECM
FA N HCooling Fan
Relay No.3
Cooling Fan
Motor No.2
Cooling Fan
Relay No.1
Cooling Fan
Motor No.1
Low Speed (Series Connection)
High Speed (Parallel Connection) Air
Conditioning
ECU
Engine Coolant
Temperature SensorFA N L
ECM
FA N HCooling Fan
Relay No.3
Cooling Fan
Motor No.2
Cooling Fan
Relay No.1
Cooling Fan
Relay No.2
Cooling Fan
Motor No.1 : CAN
Cooling Fan
Relay No.2
EG-52
8. Cooling Fan Control
On the models with air conditioning, the ECM controls the operation of the cooling fan in two speeds (Low
and High) based on the engine coolant temperature sensor signal and the air conditioning ECU signal. This
control is accomplished by operating the 2 fan motors in 2 stages through low speed (series connection) and
high speed (parallel connection).
Wiring Diagram
Cooling Fan Operation
Air Conditioning ConditionEngine Coolant Temperature C (F)
A / C CompressorRefrigerant Pressure94 (201.2) or lower95.5 (203.9) or higher
OFF1.2 MPa (12.5 kgf / cm2, 178 psi) or lowerOFFHigh
ON1.2 MPa (12.5 kgf / cm2, 178 psi) or lowerLowHighON1.2 MPa (12.5 kgf / cm2, 178 psi) or higherHighHigh
Page 75 of 2000
ENGINE - 2GR-FE ENGINE
285EG16
Oil Pan No. 1
Oil Filter Case Oil Pan No. 2EG-79
10. Oil Pan
The oil pan No. 1 is made of aluminum alloy.
The oil pan No. 2 is made of steel.
The oil pan No. 1 is secured to the cylinder block and the transmission housing and is increasing rigidity.
The oil filter case is integrated with the oil pan No. 1.
Page 91 of 2000
ENGINE - 2GR-FE ENGINE
01MEG34Y
Pulsation Damper
Fuel Filter
Fuel PumpPressure Regulator
Fuel Pump
Assembly
Fuel Tank
285EG38
Fuel Delivery PipesPulsation Damper
Holder
O-ring
Nylon TubeEG-95
2. Fuel Returnless System
This type of fuel system is used to reduce the evaporative emission. As shown below, by integrating the fuel
filter and pressure regulator with fuel pump assembly, the fuel return system in which the fuel returns from
the engine area is discontinued and temperature rise inside the fuel tank is prevented.
3. Fuel Delivery Pipe
The fuel delivery pipe made of plastic is used to realize lightweight.
The right and left fuel delivery pipes are connected by a nylon tube.
The pulsation damper is sealed with an O-ring and secured with a holder.
Page 97 of 2000

ENGINE - 2GR-FE ENGINEEG-101
ENGINE CONTROL SYSTEM
1. General
The engine control system of the 2GR-FE engine has the following features.
System
Outline
SFI
(Sequential Multiport
Fuel Injection)
[See page EG-117]
An L-type SFI system detects the intake air mass with a hot-wire type air
flow meter.
ESA
(Electronic Spark
Advance)
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 selects the optimal ignition timing in accordance with the
signals received from the sensors and sends the (IGT) ignition signal to
the igniter.
ETCS-i
(Electronic Throttle
Control
System-intelligent)
[See page EG-118]
Optimally controls the throttle valve opening in accordance with the amount
of accelerator pedal effort and the condition of the engine and the vehicle.
Dual VVT-i
(Variable Valve
Timing-intelligent)
System
[See page EG-120]
Controls the intake and exhaust camshafts to an optimal valve timing in
accordance with the engine condition.
ACIS
(Acoustic Control
Induction System)
[See page EG-126]The intake air passages are switched according to the engine speed and
throttle valve opening angle to provided high performance in all speed
ranges.
Air Intake Control
System
[See page EG-128]The intake air duct is divided into two areas, and the ECM controls the air
intake control valve and the actuator that are provided in one of the areas to
reduce the amount of engine noise.
Fuel Pump Control
[See page EG-53 in
2AZ-FE section]Fuel pump operation is controlled by signals from the ECM.
The fuel pump is stopped, when the SRS airbag is deployed in a frontal,
side, and rear side collision.
Air Conditioning Cut-off
ControlBy turning the air conditioning compressor ON or OFF in accordance with
the engine condition, drivability is maintained.
Charging Control
[See page EG-65 in
2AZ-FE section]The engine ECU regulates the charging voltage of the generator in
accordance with the driving conditions and the charging state of the battery.
Cooling Fan Control
[See page EG-129]
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.
(Continued)