heater TOYOTA RAV4 2006 Service Repair Manual

ENGINE - 2AZ-FE ENGINE
01NEG35Y
Throttle Body
To H e a t e r C o r e
To R a d i a t o r
Thermostat
From Radiator Wa t e r P u m pBypass Passage
01NEG59Y
Bypass PassageCylinder Head
Wa t e r P u m p
Cylinder Block
Thermostat
Reservoir
Ta n k
RadiatorThrottle
BodyHeater Core EG-16
COOLING SYSTEM
The cooling system uses a pressurized forced-circulation system with pressurized reservoir tank.
A thermostat with a bypass valve is located on the water inlet housing to maintain suitable temperature
distribution in the cooling system.
An aluminum radiator core is used for weight reduction.
The flow of the engine coolant makes a U-turn in the cylinder block to ensure a smooth flow of the engine
coolant. In addition, a bypass passage is enclosed in the cylinder head and the cylinder block.
Warm water from the engine is sent to the throttle body to prevent freeze-up.
The TOYOTA genuine Super Long Life Coolant (SLLC) is used.
System Diagram

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
01MEG04Y
SENSORSACTUATORS
MASS AIR FLOW METER
INTAKE AIR TEMPERATURE
SENSOR
ENGIEN COOLANT
TEMPERATURE SENSOR
THROTTLE POSITION
SENSOR
CRANKSHAFT POSITION
SENSOR
CAMSHAFT POSITION
SENSOR
ACCELERATOR PEDAL
POSITION SENSOR
AIR-FUEL RATIO SENSOR
(Bank 1, Sensor 1)
HEATED OXYGEN SENSOR
(Bank 1, Sensor 2)
KNOCK SENSOR
COMBINATION METER
Vehicle Speed Signal
IGNITION SWITCH
Ignition Signal
Starter Signal
PA R K / N E U T R A L P O S I T I O N
SWITCH
TRANSMISSION CONTROL
SWITCH
CRUISE CONTROL SWITCHVG
THA
THW
VTA1
VTA2
NE
G2
VPA
VPA2
A1A
OX1B
KNK1
SPD
IGSW
STA
D, 2, L
R, P, N
3
CCSECM#10
#20
#30
#40
IGT1 IGT4
IGF1
M
OC1
FC
HA1A
HT1BSFI
No.1 INJECTOR
No.2 INJECTOR
No.3 INJECTOR
No.4 INJECTOR
ESA
IGNITION COIL
with IGNITER
SPARK PLUGS
ETCS-i
THROTTLE CONTROL
MOTOR
VVT-i
CAMSHAFT TIMING OIL
CONTROL VALVE
FUEL PUMP CONTROL
CIRCUIT OPENING
RELAY
AIR-FUEL RATIO AND
HEATED OXYGEN SENSOR
HEATER CONTROL
AIR-FUEL RATIO SENSOR
HEATER (Bank1, Sensor1)
HEATED OXYGEN SENSOR
HEATER (Bank1, Sensor2)
EG-32
2. Construction
The configuration of the engine control system in the 2AZ-FE engine is shown in the following chart.
(Continued)

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
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 - 2GR-FE ENGINE
285EG27
Air Bleeder PlugTo Throttle Body
From Throttle Body
To H e a t e r
From Heater
To Radiator
From Radiator Thermostat
Opening Temperature:
80 - 84
C (176 - 183F)
01MEG35Y
ThermostatBypass Pipe
Heater Return Pipe
Air Bleeder Plug
Cylinder Head
Cylinder Block
Wa t e r P u m p
Radiator
Throttle
Body
Heater
Reservoir
Ta n k
EG-88
COOLING SYSTEM
1. General
The cooling system is a pressurized, forced-circulation type.
A thermostat with a bypass valve is located on the water inlet housing to maintain suitable temperature
distribution in the cooling system.
A cooling fan control system in which the ECM optimally controls cooling fan speed is used. For details,
see page EG-129.
An air bleeder plug is provided on the water inlet assembly to improve the efficiency of changing the
engine coolant. For details, refer to the 2006 RAV4 Repair Manual (Pub. No. RM01M1U).
The TOYOTA genuine SLLC (Super Long Life Coolant) is used for the engine coolant.
System Diagram

ENGINE - 2GR-FE ENGINE EG-102
System
Outline
Air-fuel Ratio Sensor and
Oxygen Sensor Heater
ControlMaintains the temperature of the air-fuel ratio sensor or oxygen sensor at an
appropriate level to increase accuracy of detection of the oxygen
concentration in the exhaust gas.
Evaporative Emission
Control
[See page EG-131]
The ECM controls the purge flow of evaporative emission (HC) in the
canister in accordance with engine conditions.
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 EVAP control system pressure.
Engine ImmobilizerProhibits fuel delivery and ignition if an attempt is made to start the engine
with an invalid ignition key.
Diagnosis
[See page EG-132]When the ECM detects a malfunction, the ECM diagnoses and memorizes
the failed section.
Fail-safe
[See page EG-133]When the ECM detects a malfunction, the ECM stops or controls the engine
according to the data already stored in the memory.

ENGINE - 2GR-FE ENGINE
01MEG06Y
COMBINATION METER
Vehicle Speed Signal
AIR-FUEL RATIO SENSOR
Bank 1, Sensor 1
Bank 2, Sensor 1
HEATED OXYGEN SENSOR
Bank 1, Sensor 2
Bank 2, Sensor 2
CANISTER PUMP MODULE
CANISTER PRESSURE
SENSOR
PARK / NEUTRAL POSITION
SWITCH
TRANSMISSION CONTROL
SWITCH
TRANSPONDER KEY ECU
GENERATOR
BATTERY CURRENT SENSOR
(BUILT-IN BATTERY
TEMPERATURE SENSOR)
WIPER CONTROL SWITCHSPD
A1A
A2A
OX1B
OX2B
PPMP
STA
P, R, N, D
4, L
IMI
IMO
DF
THB VCIB
INHECMACIS
AICV
FC
FPR
HA1A
HA2A
HT1B
HT2B
RLOACIS
ACIS ACTUATOR
AIR INTAKE CONTROL
SYSTEM
VSV
FUEL PUMP CONTROL
CIRCUIT OPENING RELAY
FUEL PUMP RELAY
AIR-FUEL RATIO SENSOR
HEATER CONTROL
AIR-FUEL RATIO SENSOR
HEATER
Bank 1, Sensor 1
Bank 2, Sensor 1
HEATED OXYGEN SENSOR
HEATER CONTROL
HEATED OXYGEN SENSOR
HEATER
Bank 1, Sensor 2
Bank 2, Sensor 2
CHARGING CONTROL
GENERATOR EG-104
(Continued)

ENGINE - 2GR-FE ENGINEEG-109
5. Main Components of Engine Control System
General
The main components of the 2GR-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
Intake VVT Sensor (Rotor Teeth)MRE (Magnetic Resistance Element)
Ty p e ( 3 )2
Exhaust VVT Sensor (Rotor Teeth)MRE (Magnetic Resistance Element)
Ty p e ( 3 )2
Accelerator Pedal Position SensorNon-contact Type1
Throttle Position SensorNon-contact Type1
Knock SensorBuilt-in Piezoelectric Type
(Non-resonant Type / Flat Type)2
Air fuel Ratio Sensor(Bank 1, Sensor 1)Type with Heater (Planar Type)1 eachAir-fuel Ratio Sensor(Bank 2, Sensor 1)Type with Heater (Planar Type)1 each
Heated Oxygen (Bank 1, Sensor 2)Type with Heater (Cup Type)1 eachHeated Oxygen
Sensor
(Bank 2, Sensor 2)Type with Heater (Cup Type)1 each
Injector12-hole Type6

ENGINE - 2GR-FE ENGINEEG-133
15. Fail-safe
When the ECM detects a malfunction, the ECM stops or controls the engine according to the date already
stored in the memory.
Fail-safe Chart
DTC No.Fail-safe OperationFail-safe Deactivation Conditions
P0031, P0032,
P0051, P0052ECM turns off air-fuel ratio sensor heater.Ignition switch OFF.
P0037, P0038,
P0057, P0058ECM turns off heated oxygen sensor heater.Ignition switch OFF.
P0100, P0102,
P0103Ignition timing is calculated from engine speed
and throttle angle.“Pass” condition detected.
P0110, P0112,
P0113Intake air temperature is fixed at 20C (68F).“Pass” condition detected.
P0115, P0117,
P0118Engine coolant temperature is fixed at 80C
(176
F).“Pass” condition detected.
P0120, P0121,
P0122, P0123,
P0220, P0222,
P0223, P0604,
P0606, P0607,
P0657, P2102,
P2103, P2111,
P2112, P2118,
P2119, P2135
If ETCS-i (Electronic Throttle Control
System-intelligent) has a malfunction, ECM
cuts off current to throttle control motor.
Throttle control valve returns to predetermined
opening angle (approximately 6.5
) by force of
return spring. ECM then adjusts engine output
by controlling fuel injection (intermittent
fuel-cut) and ignition timing in accordance with
accelerator pedal opening angel to enable
vehicle to continue driving at minimal speed. If
accelerator pedal is depressed firmly and
slowly, vehicle can be driven slowly. If
accelerator pedal is depressed quickly, vehicle
may speed up and slow down erratically.If “Pass” condition is detected and
then the ignition switch is turned
OFF, fail-safe operation will stop
and system will return to normal
operating conditions.
P0327, P0328,
P0332, P0333Max. timing retardation.Ignition switch OFF.
P0351, P0352,
P0353, P0354,
P0355, P0356
Fuel is cut.“Pass” condition detected.
P2120, P2121,
P2122, P2123,
P2125, P2127,
P2128, P2138
Accelerator pedal position sensor has two (main
and sub) sensor circuits. If a malfunction occurs
in either of sensor circuits, ECM detects
abnormal signal voltage difference between two
sensor circuits and switches into limp mode. In
limp mode, remaining circuit is used to calculate
accelerator pedal opening to allow vehicle to
continue driving. If both circuits malfunction,
ECM regards opening angle of accelerator pedal
to be fully closed. In this case, throttle valve will
remain closed as if engine is idling.
If “Pass” condition is detected and
then the ignition switch is turned
OFF, fail-safe operation will stop
and system will return to normal
operating conditions.