air condition TOYOTA RAV4 2006 Service Repair Manual

ENGINE - 2AZ-FE ENGINE
DR011EG22 01NEG26Y
Air Flow During Engine Revolution
Wa t e r P u m p
Swirl Chamber
Crankshaft
Bearing Cap
Plastic Region
Tightening BoltsThermostat Housing
Air Conditioning
Compressor BracketsAir Passage Holes
Air Flow
NOTICE
Never attempt to machine the cylinder because it has a thin liner thickness.
EG-7
4. Cylinder Block
Lightweight aluminum alloy is used for the cylinder block.
By producing the thin cast-iron liners and cylinder block as a unit, compaction is realized.
Air passage holes are provided in the crankshaft bearing area of the cylinder block. As a result, the air at
the bottom of the cylinder flows smoother, and pumping loss (back pressure at the bottom of the piston
generated by the piston’s reciprocal movement) is reduced to improve the engine’s output.
The oil filter and the air conditioning compressor brackets are integrated into the crankcase. Also, the
water pump swirl chamber and thermostat housing are integrated into the cylinder block.

ENGINE - 2AZ-FE ENGINE
240EG98
Idler Pulley for Automatic Tensioner
Generator Pulley
Water Pump Pulley
Air Conditioning
Compressor Pulley Crankshaft Pulley Idler Pulley
258RV77
ArmIdler Pulley
Te n s i o n e r
A - A Cross SectionAAEG-29
SERPENTINE BELT DRIVE SYSTEM
1. General
Accessory components are driven by a serpentine belt consisting of a single V-ribbed belt. It reduces the
overall engine length, weight and the number of engine parts.
An automatic tensioner eliminates the need for tension adjustment.
2. Automatic Tensioner
The automatic tensioner consists of an idler pulley and a tensioner. The idler pulley maintains belt tension
by the force of the spring that is located in the tensioner.

ENGINE - 2AZ-FE ENGINE EG-30
ENGINE CONTROL SYSTEM
1. General
The engine control system for the 2AZ-FE engine has the following systems.
System
Outline
SFI
Sequential Multiport
Fuel InjectionAn L-type SFI system directly detects the intake air volume with a hot-wire
type mass air flow meter.
The fuel injection system is a sequential multiport fuel injection system.
ESA
Electronic Spark
AdvanceIgnition timing is determined by the ECM based on signals from various sensors.
The ECM corrects ignition timing in response to engine knocking.
ETCS-i
Electronic
Optimally controls the throttle valve opening in accordance with the amount of
accelerator pedal effort and the condition of the engine and the vehicle.
Electronic
Throttle Control
System-intelligent
(See page-43)A linkless-type is used, without an accelerator cable.
An accelerator pedal position sensor is provided on the accelerator pedal.
A non-contact type throttle position sensor and accelerator pedal position
sensor are used.
VVT-i
Va r i a b l e Va l v e
Timing-intelligent
(See page EG-48)
Controls the intake camshaft to an optimal valve timing in accordance with the
engine condition.
Air-fuel Ratio
Sensor, Oxygen
Sensor Heater
ControlMaintains the temperature of the air-fuel ratio sensor or oxygen sensor at an
appropriate level to realize accuracy of detection of the oxygen concentration in
the exhaust gas.
Air Conditioning
Cut-off ControlBy turning the air conditioning compressor ON or OFF in accordance with the
engine condition, drivability is maintained.
Cooling Fan Control
(See page EG-52)Radiator cooling fan operation is controlled by signals from ECM based on the
engine coolant temperature sensor signal and the condition of the air
conditioning operation.
Fuel Pump Control
(See page EG-53)Fuel pump operation is controlled by signal from the ECM.
The fuel pump is stopped when the SRS driver’s and front passenger’s airbags
are deployed.
Evapotative Emission
The ECM controls the purge flow of evaporative emissions (HC) in the canister
in accordance with engine conditions.
Evapotative Emission
Control
(See page EG-54)Approximately five hours after the ignition switch has been turned OFF, the
ECM operates the canister pump module to detect any evaporative emission
leakage occurring in the EVAP (evaporative emission) control system through
changes in the 0.02 in. leak pressure.
Charging Control
(See page EG-65)The ECM regulates the charging voltage of the generator in accordance with the
driving conditions and the charging state of the battery.
(Continued)

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

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

ENGINE - 2AZ-FE ENGINE
Throttle Body
Throttle Position
Sensor Portion
Reduction
Gears
Throttle ValveMagnetic Yoke
Hall IC
Throttle Control
Motor A
View from A
Cross Section
01NEG44Y
EG-44
Construction
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 ratio control of the direction and the amperage of the current that
flows to the throttle control motor in order to regulate the opening of the throttle valve.
Operation
1) General
The ECM drives the throttle control motor by determining the target throttle valve opening in accordance
with the respective operating condition.
Non-linear Control
Idle Air Control
TRAC Throttle Control
VSC Coordination Control
Cruise Control

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.

ENGINE - 2AZ-FE ENGINE
DR011EG25
Camshaft Position Sensor
Engine Coolant
Temperature Sensor
Crankshaft
Position Sensor
Camshaft Timing
Oil Control Valve
Throttle Position
Sensor
ECM
Mass Air Flow Meter Vehicle Speed Signal
221EG16
Crankshaft Position Sensor
Mass Air Flow Meter
Throttle Position Sensor
Engine Coolant Temp. Sensor
Camshaft Position Sensor
Vehicle Speed SignalECM
Target Valve Timing
Feedback
Correction
Actual Valve Timing
Duty-cycle
Control
Camshaft Timing
Oil Control Valve
EG-48
7. VVT-i (Variable Valve Timing-intelligent) System
General
The VVT-i system is designed to control the intake camshaft within a range of 40 (of Crankshaft Angle)
to provide valve timing that is optimally suited to the engine condition. This realizes proper torque in
all the speed ranges as well as realizing excellent fuel economy, and reducing exhaust emissions.
Using the engine speed signal, vehicle speed signal, and the signals from mass air flow meter, throttle
position sensor and engine coolant temperature sensor, 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 crankshaft position sensor to detect the actual valve timing,
thus providing feedback control to achieve the target valve timing.

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

ENGINE - 2AZ-FE ENGINE
Service Tip
The canister pump module performs the EVAP leak check. This check is done approximately five
hours after the engine is turned off. So you may hear sound coming from underneath the luggage
compartment for several minutes. It does not indicate a malfunction.
The pinpoint pressure test procedure is carried out by pressurizing the fresh air line that runs from
the pump module to the air filler neck. For details, refer to the 2006 RAV4 Repair Manual (Pub.
No. RM01M1U).
EG-54
10. EVAP (evaporative Emission) Control System
General
The EVAP (evaporative emission) control system prevents the vapor gas that is created in the fuel tank from
being released directly into the atmosphere.
The canister stores the vapor gas that has been created in the fuel tank.
The ECM controls the purge VSV in accordance with the driving conditions in order to direct the vapor
gas into the engine, where it is burned.
In this system, the ECM checks the evaporative emission leak and outputs DTC (Diagnostic Trouble
Code) in the event of a malfunction. An EVAP (evaporative emission) leak check consists of an
application of a vacuum pressure to the system and monitoring the changes in the system pressure in order
to detect a leakage.
This system consists of the purge VSV, canister, refueling valve, canister pump module, and ECM.
The ORVR (Onboard Refueling Vapor Recovery) function is provided in the refueling valve.
The canister pressure sensor has been included to the canister pump module.
The canister filter has been provided on the fresh air line. This canister filter is maintenance-free.
The followings are the typical conditions for enabling an EVAP leak check:
Typical Enabling
Condition
Five hours have elapsed after the engine has been turned OFF*.
Altitude: Below 2400 m (8000 feet)
Battery voltage: 10.5 V or more
Ignition switch: OFF
Engine coolant temperature: 4.4 to 35C (40 to 95F)
Intake air temperature: 4.4 to 35C (40 to 95F)
*: If engine coolant temperature does not drop below 35C (95F), this time should be extended to 7hours.
Even after that, if the temperature is not less than 35
C (95F), the time should be extended to 9.5 hours.