TOYOTA RAV4 2006 Service Owner's Guide

ENGINE - 2AZ-FE ENGINE
01MEG09Y
Accelerator Pedal
Position Sensor
Generator
MIL
DLC3Park / Neutral
Position Switch
Ignition
Switch
Circuit Opening RelayECM
Battery
Throttle
Position
Sensor
Throttle
Control
Motor
Purge VSVMass Air Flow Meter
Intake Air Temperature
Sensor
Camshaft Position
Sensor
Camshaft
Timing
Oil Control
Va l v e
Ignition Coil
with Igniter
Injector
Knock Sensor
Engine
Coolant
Temperature
Sensor
Crankshaft Position
Sensor
Canister
Filter
Fuel Pump
Canister Pump Module
Ve n t Va l v e
Leak Detection Pump
Canister Pressure SensorTWCs
Heated Oxygen Sensor
(Bank 1, Sensor 2)
Air-fuel Ratio Sensor
(Bank 1, Sensor 1) EG-34
3. Engine Control System Diagram

ENGINE - 2AZ-FE ENGINE
01MEG31Y
DLC3
Accelerator Pedal
Position Sensor
Mass Air Flow Meter
(Built-in Intake Air
Temperature Sensor)
VSV (for EVAP)
Battery Current
Sensor
Fuel Pump
Canister Pump Module
Ve n t Va l v e
Leak Detection Pump
Canister Pressure Sensor
ECM
Heated Oxygen Sensor
(Bank 1, Sensor 2) Air Fuel Ratio Sensor
(Bank 1, Sensor 1)
Camshaft Timing
Oil Control ValveInjectorKnock Sensor
Ignition Coil with Igniter
Throttle Position
Sensor
Camshaft Position
Sensor
Water Temperature
Sensor
Crakshaft Position
SensorEG-35
4. Layout of Main Components

ENGINE - 2AZ-FE ENGINE EG-36
5. Main Components of Engine Control System
General
The main components of the 2AZ-FE engine control system are as follows:
Component
OutlineQuantity
ECM32-bit CPU1
Mass Air Flow MeterHot-wire Type1
Crankshaft Position Sensor (Rotor Teeth)Pick-up Coil Type (36-2)1
Camshaft Position Sensor (Rotor Teeth)Pick-up Coil Type (3)1
Throttle Position SensorNon-contact Type1
Accelerator Pedal Position SensorNon-contact Type1
Knock SensorBuilt-in Piezoelectric Element Type
(Flat Type)1
Air-fuel Ratio Sensor
(Bank 1, Sensor 1)Type with Heater
(Planar Type)1
Heated Oxygen Sensor
(Bank 1, Sensor 2)Type with Heater
(Cup Type)1
Injector12-hole Type4
ECM
The 32-bit CPU of the ECM is used to increase the speed for processing the signals.

ENGINE - 2AZ-FE ENGINE
00REG21Y
D13N11
Air-fuel
Ratio
SensorA1A+
(3.3V)
A1A -
(2.9V)ECMHeated
Oxygen
SensorOX1B
EX1BECM
Air-fuel Ratio Sensor Circuit Heated Oxygen Sensor
: Air-fuel Ratio Sensor
: Heated Oxygen Sensor
Air-fuel Ratio Sensor Data
Displayed on Hand-held
Te s t e r4.2
2.2
11 (Rich) 14.7 19 (Lean)0.11
Heated Oxygen
Sensor Output (V)
Air-fuel RatioEG-37
Air-fuel Ratio Sensor and Heated Oxygen Sensor
1) General
The air-fuel ratio sensor and heated oxygen sensor differ in output characteristics.
Approximately 0.4V is constantly applied to the air-fuel ratio sensor, which outputs an amperage that
varies in accordance with the oxygen concentration in the exhaust emission. The ECM converts the
changes in the output amperage into voltage in order to linearly detect the present air-fuel ratio. The
air-fuel ratio sensor data is read out by the hand-held tester.
The output voltage of the heated oxygen sensor changes in accordance with the oxygen concentration
in the exhaust emission. The ECM uses this output voltage to determine whether the present air-fuel
ratio is richer or leaner than the stoichiometric air-fuel ratio.

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.

ENGINE - 2AZ-FE ENGINE
214CE04
: Conventional Type
: Flat Type
(V)
Vo l t a g e
Frequency (Hz)A
BA: Detection Band of
Conventional Type
B: Detection Band of
Flat Type
Characteristic of Knock Sensor
214CE01214CE02
Steel Weight
Insulator
Piezoelectric
ElementOpen / Short Circuit
Detection Resistor
Flat Type Knock Sensor
(Non-resonant Type)Piezoelectric
Element
Vibration Plate
Conventional Type Knock Sensor
(Resonant Type)EG-39
Knock Sensor (Flat Type)
1) General
In the conventional type knock sensor (resonant type), a vibration plate which has the same resonance
point as the knocking frequency of the engine is built in and can detect the vibration in this frequency
band.
On the other hand, a flat type knock sensor (non-resonant type) has the ability to detect vibration in a
wider frequency band from about 6 kHz to 15 kHz, and has the following features.
The engine knocking frequency will change a bit depending on the engine speed. The flat type knock
sensor can detect the vibration even when the engine knocking frequency is changed. Thus the
vibration detection ability is increased compared to the conventional type knock sensor, and a more
precise ignition timing control is possible.
2) Construction
The flat type knock sensor is installed on the engine through the stud bolt installed on the cylinder
block. For this reason, a hole for the stud bolt is running through the center of the sensor.
Inside of the sensor, a steel weight is located on the upper portion and a piezoelectric element is located
under the weight through the insulator.
The open / short circuit detection resistor is integrated.

ENGINE - 2AZ-FE ENGINE
214CE08
Steel Weight
Inertia
Piezoelectric
Element
214CE06
Knock Sensor
200 k
Piezoelectric
ElementOpen / Short Circuit
Detection ResistorKNK1
EKNKECM
5 V
200 k
IC
Service Tip
In accordance with the adoption of an open / short circuit detection resistor, the inspection
method for the sensor has been changed. For details, refer to the 2006 RAV4 Repair Manual
(Pub. No. RM01M1U).
To prevent the water accumulation in the connecter, make sure to install the flat type knock
sensor in the position as shown in the following illustration.
251EG12
10
10
Knock Sensor EG-40
3) Operation
The knocking vibration is transmitted to the
steel weight and its inertia applies pressure to
the piezoelectric element. The action
generates electromotive force.
4) Open / Short Circuit Detection Resistor
While the ignition is ON, the open / short circuit detection resistor in the knock sensor and the resistor
in the ECM keep constant the voltage at the terminal KNK1 of engine.
An IC (Integrated Circuit) in the ECM is always monitoring the voltage of the terminal KNK1. If the
open / short circuit occurs between the knock sensor and the ECM, the voltage of the terminal KNK1 will
change and the ECM detects the open / short circuit and stores DTC (Diagnostic Trouble Code).

ENGINE - 2AZ-FE ENGINE
01NEG43Y
238EG79
230LX12
Throttle Body
Throttle Position
Sensor Portion
Throttle Control
MotorMagnetic
Yo k e
Hall IC
Cross Section
Throttle Position
Sensor
Magnetic Yoke
Hall
IC
Hall
IC
VTA1
ETA
VCTA
VTA2ECMOutput
Voltage(V)
5
0
Fully Close10 90 (
)
Fully Open VTA2
VTA1
Throttle Valve Opening Angle
Service Tip
The inspection method differs from the conventional contact type throttle position sensor because
this non-contact type sensor uses a Hall IC.
For details, refer to the 2006 RAV4 Repair Manual (Pub. No. RM01M1U).
EG-41
Throttle Position Sensor
The throttle position sensor is mounted on the throttle body to detect the opening angle of the throttle valve.
The throttle position sensor converts the magnetic flux density that changes when the magnetic yoke
(located on the same axis as the throttle shaft) rotates around the Hall IC into electric signals to operate the
throttle control motor.

ENGINE - 2AZ-FE ENGINE
00SEG39Y
228TU25 228TU24
A
AInternal Construction
A - A Cross SectionAccelerator
Pedal Arm
Hall IC
Magnetic Yoke
Accelerator Pedal
Position Sensor
Magnetic Yoke
Hall
IC
Hall
IC
VPA
EPA
VCPA
VPA2
EPA2ECM
Output
Voltage(V)
5
0VPA2
VPA
Fully Close Fully Open90
Accelerator Pedal Depressed Angle VCP2
Service Tip
The inspection method differs from the conventional contact type accelerator pedal position sensor
because this non-contact type sensor uses a Hall IC.
For details, refer to the 2006 RAV4 Repair Manual (Pab. No. RM01M0U).
EG-42
Accelerator Pedal Position Sensor
The non-contact type accelerator pedal position sensor uses a Hall IC.
The magnetic yoke that is mounted at the accelerator pedal arm rotates around the Hall IC in accordance
with the amount of effort that is applied to the accelerator pedal. The Hall IC converts the changes in the
magnetic flux at that time into electrical signals, and outputs them as accelerator pedal effort to the ECM.
The Hall IC contains circuits for the main and sub signals. It converts the accelerator pedal depressed
angles into electric signals with two differing characteristics and outputs them to the ECM.

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