2001 TOYOTA PRIUS Fuel injection

*The titles given inside the components are the names of the terminals (terminal codes) and are not treated as being
abbreviations.
2001 PRIUS (EWD414U)
ABBREVIATIONS D
ABBREVIATIONS
The following abbreviations are used in this manual.
ABS = Anti±Lock Brake System
A/C = Air Conditioning
COMB. = Combination
DC = Direct Current
ECU = Electronic Control Unit
EMPS = Electric Motor Power Steering
ESA = Electronic Spark Advance
EVAP = Evaporative Emission
HV = Hybrid Vehicle
J/B = Junction Block
LH = Left±Hand
PTC = Positive Temperature Coefficient
R/B = Relay Block
RH = Right±Hand
SFI = Sequential Multiport Fuel Injection
SRS = Supplemental Restraint System
SW = Switch
TEMP. = Temperature
VSV = Vacuum Switching Valve
w/ = With
w/o = Without

2001 PRIUS (EWD414U)
ENGINE CONTROL
This system utilizes an engine control module and maintains overall control of the engine, transmission and so on. An outline
of the engine control is explained here.
1. INPUT SIGNALS
(1) Engine coolant temp. signal circuit
The engine coolant temp. sensor detects the engine coolant temp. and has a built±in thermistor with a resistance which
varies according to the engine coolant temp. thus the engine coolant temp. is input in the form of a control signal into
TERMINAL THW of the engine control module.
(2) Intake air temp. signal circuit
The intake air temp. sensor is installed in the mass air flow meter and detects the intake air temp., which is input as a
control signal into TERMINAL THA of the engine control module.
(3) Oxygen sensor signal circuit
The oxygen density in the exhaust gases is detected and input as a control signal into TERMINALS OX1A and OX1B of
the engine control module.
(4) RPM signal circuit
Camshaft position and crankshaft position are detected by the camshaft position sensor and crankshaft position sensor.
Camshaft position is input as a control signal to TERMINAL G2 of the engine control module, and engine RPM is input
into TERMINAL NE+.
(5) Throttle signal circuit
The throttle position sensor detects the throttle valve opening angle, which is input as a control signal into TERMINALS
VTA and VTA2 of the engine control module.
(6) Vehicle speed signal circuit
The vehicle speed signal from brake ECU, detects the vehicle speed and inputs a control signal into TERMINAL SPD of
the engine control module via the combination meter.
(7) Battery signal circuit
Voltage is constantly applied to TERMINAL BATT of the engine control module. When the ignition SW is turned on, the
voltage for engine control module start±up power supply is applied to TERMINAL +B of the engine control module via
EFI relay.
(8) Engine knock signal circuit
Engine knocking is detected by knock sensor and the signal is input into TERMINAL KNK1 of the engine control module
as a control signal.
2. CONTROL SYSTEM
*SFI system
The SFI system monitors the engine condition through the signals, which are input from each sensor to the engine
control module. The best fuel injection volume is decided based on this data and the program memorized by the engine
control module, and the control signal is output to TERMINALS #10, #20, #30 and #40 of the engine control module to
operate the injector. (Inject the fuel). The SFI system produces control of fuel injection operation by the engine control
module in response to the driving conditions.
*ESA system
The ESA system monitors the engine condition through the signals, which are input to the engine control module from
each sensor. The best ignition timing is detected according to this data and the memorized data in the engine control
module, and the control signal is output to TERMINALS IGT1, IGT2, IGT3 and IGT4. This signal controls the ignition coil
and igniter to provide the best ignition timing for the driving conditions.
*Fuel pump control system
The engine control module operation outputs to TERMINAL FC and controls the CIR OPN relay. Thus controls the fuel
pump drive speed in response to conditions.
3. DIAGNOSIS SYSTEM
With the diagnosis system, when there is a malfunctioning in the engine control module signal system, the malfunction
system is recorded in the memory. The malfunctioning system can then be found by reading the display (Code) of the
malfunction indicator lamp.
4. FAIL±SAFE SYSTEM
When a malfunction occurs in any system, if there is a possibility of engine trouble being caused by continued control based
on the signals from that system, the fail±safe system either controls the system by using data (Standard values) recorded in
the engine control module memory or else stops the engine.
SYSTEM OUTLINE

ENGINE ± 1NZ-FXE ENGINE62
ENGINE CONTROL SYSTEM
1. General
The engine control system for the 1NZ-FXE engine has following system.
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.
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.
VVT-i
Variable Valve
Timing-intelligentControls the intake camshaft to an optimal valve timing in accordance with
the engine condition.
ETCS-i
Electronic
Throttle Control
System-intelligentOptimally controls the throttle valve opening in accordance with the ECM,
and the conditions of the engine and the vehicle, and comprehensively
controls the ISC and cruise control system.
Fuel Pump Control
Fuel pump operation is controlled by signal from the ECM.

To stop the fuel pump during operation of the SRS airbag.
Oxygen Sensor Heater
ControlMaintains the temperature of the oxygen sensors at an appropriate level to
increase accuracy of detection of the oxygen concentration in the exhaust gas.
Evaporative Emission
Control

The ECM controls the purge flow of evaporative emissions (HC) in the
charcoal canister in accordance with engine conditions.

Using 3 VSVs and a vapor pressure sensor, the ECM detects any
evaporative emission leakage occurring between the fuel tank and the
charcoal canister, and vapor reducing fuel tank through the changes in the
tank pressure. For details, see page 79.
Toyota HCAC System
The ECM controls the VSV (for Toyota HCAC System) to improve the clean
emission performance of the exhaust gas when the temperature of the TWC
is low. For details, see page 58.
Air Conditioning
Cut-Off ControlBy turning the air conditioning compressor OFF in accordance with the
engine condition, drivability is maintained.
Cooling Fan ControlRadiator cooling fan operation is controlled by signals from ECM based on
the engine coolant temperature sensor signal (THW).
HV Immobiliser
Prohibits fuel delivery, ignition, and starting the HV system if an attempt is
made to start the HV system with an invalid ignition key. For details, see page
80.
DiagnosisWhen the ECM detects a malfunction, the ECM diagnoses and memorizes
the failed section.
Fail-SafeWhen the ECM detects a malfunction, the ECM stops or controls the engine
according to the data already stored in memory.

THS (TOYOTA HYBRID SYSTEM)
HV ECUGO
ECM
Engine
Throttle Control
Motor
SPDO
EF1
HTE, ETH
ESA
VVT-i
W
MESTP
Brake Actuator
(Brake Master
Cylinder)
BRAKE ECUBrake Actuator
(Solenoid Valves)
Pressure Sensors
Signal
HV ECU Pressure
BTH
Total Brake Force
RequestedHTB
Regenerative Brake
Force Transmitted29
3. ECM Control
The ECM receives the demand torque and the target rpm which were sent from HV ECU (THE, ETH), and
controls the degree of throttle valve opening, fuel injection timing, ignition time and VVT-i.
In addition, the actual rpm is sent to the HV ECU with GO, and the speed signal from the hybrid transaxle
is received through HV ECU with SPDO.
When the vehicle is stopped, the HV ECU may send an engine stop (ESTP) command to the ECM to reduce
fuel used.
When a malfunction occurs in the system, the ECM activates MIL via the directions from the HV ECU.
4. BRAKE ECU Control
The brake ECU calculates the total braking force needed, based on the master cylinder pressure in the brake
actuator generated when the driver depresses the brake pedal, and sends this valve to the HV ECU.
The HV ECU computes a part for the regeneration brake force from the total braking force, and sends the
result to the brake ECU.
The HV ECU executes to the minus torque to MG2, and carries out the regenerative brake functions.
The brake ECU controls the brake actuator solenoid valves and generates the wheel cylinder pressure, which
is the regenerative brake force subtracted from the total braking force.

BODY ELECTRICAL ± METER
182BE07
Combination Meter
Sender
Gauge
Meter
ECU
Inclination Sensors
Temperature Signal
Sender
Gauge Signal Fuel Injection
Signal
ECM
Body ECU
Sender
Gauge Signal
Fuel TankAmbient
Temperature Sensor
Fuel Sender Gauge
Main Tank Sub Tank Fuel Pump 148
Fuel Gauge
For the purpose of correcting the calculation of the fuel level by the meter ECU, two inclination sensors
that detect the vehicle's longitudinal and latitudinal inclinations have been provided in the meter ECU, and
an ambient temperature sensor has been provided in the fuel tank to detect the temperature in the fuel tank.
The fuel level is calculated by the meter ECU in accordance with the signals of the sender gauge located
in the sub tank that have been received via the body ECU, and the fuel injection signals received from the
ECM. At this time, corrections are made by the signals from the inclination sensors that detect the vehicle's
longitudinal and latitudinal inclinations and the ambient temperature sensor that detects the temperature in
the fuel tank.

± INTRODUCTIONTERMS
IN±47
47 Author: Date:
2001 PRIUS (RM778U) CW
Curb Weight
DCDirect Current
DEFDefogger
DFLDeflector
DIFF.Differential
DIFF. LOCKDifferential Lock
D/INJDirect Injection
DLIDistributorless Ignition
DOHCDouble Over Head Cam
DPDash Pot
DSDead Soak
DSPDigital Signal Processor
EBDElectronic Brake Force Distribution
ECAMEngine Control And Measurement System
ECDElectronic Controlled Diesel
ECDYEddy Current Dynamometer
ECUElectronic Control Unit
EDElectro±Deposited Coating
EDICElectric Diesel Injection Control
EDUElectronic Driving Unit
EFIElectronic Fuel Injection
E/GEngine
EGR±VMEgr±Vacuum Modulator
ELREmergency Locking Retractor
EMPSElectric Motor Power Steering
ENGEngine
ESAElectronic Spark Advance
ETCSElectronic Throttle Control System
EVPEvaporator
E±VRVElectric Vacuum Regulating Valve
EXHExhaust
FEFuel Economy
FFFront±Engine Front±Wheel±Drive
F/GFuel Gage
FIPGFormed In Place Gasket
FLFusible Link
F/PFuel Pump
FPUFuel Pressure Up
FrFront
FRFront±Engine Rear±Wheel±Drive
F/WFlywheel
FW/DFlywheel Damper
FWDFront±Wheel±Drive
GASGasoline
GNDGround
HACHigh Altitude Compensator

± INTRODUCTIONTERMS
IN±49
49 Author: Date:
2001 PRIUS (RM778U) N
Neutral
NANatural Aspiration
No.Number
O/DOverdrive
OEMOriginal Equipment Manufacturing
OHCOverhead Camshaft
OHVOverhead Valve
OPTOption
O/SOversize
P & BVProportioning And Bypass Valve
PCSPower Control System
PCVPositive Crankcase Ventilation
PKBParking Brake
PPSProgressive Power Steering
PSPower Steering
PTOPower Take±Off
R & PRack And Pinion
R/BRelay Block
RBSRecirculating Ball Type Steering
R/FReinforcement
RFSRigid Front Suspension
RHRight±Hand
RHDRight±Hand Drive
RLYRelay
ROMRead Only Memory
RrRear
RRRear±Engine Rear±Wheel Drive
RRSRigid Rear Suspension
RWDRear±Wheel Drive
SDNSedan
SENSensor
SICSStarting Injection Control System
SOCState Of Charge
SOHCSingle Overhead Camshaft
SPECSpecification
SPISingle Point Injection
SRSSupplemental Restraint System
SSMSpecial Service Materials
SSTSpecial Service Tools
STDStandard
STJCold±Start Fuel Injection
SWSwitch
SYSSystem
T/ATransaxle
TACHTachometer
TBIThrottle Body Electronic Fuel Injection

IN0CI±02
± INTRODUCTIONTERMS
IN±51
2001 PRIUS (RM778U)
GLOSSARY OF SAE AND TOYOTA TERMS
This glossary lists all SAE±J1930 terms and abbreviations used in this manual in compliance with SAE rec-
ommendations, as well as their TOYOTA equivalents.
SAE
ABBREVIATIONSSAE TERMSTOYOTA TERMS
( )±±ABBREVIATIONS
A/CAir ConditioningAir Conditioner
ACLAir CleanerAir Cleaner, A/CL
AIRSecondary Air InjectionAir Injection (AI)
APAccelerator Pedal±
B+Battery Positive Voltage+B, Battery Voltage
BAROBarometric PressureHAC
CACCharge Air CoolerIntercooler
CARBCarburetorCarburetor
CFIContinuous Fuel Injection±
CKPCrankshaft PositionCrank Angle
CLClosed LoopClosed Loop
CMPCamshaft PositionCam Angle
CPPClutch Pedal Position±
CTOXContinuous Trap Oxidizer±
CTPClosed Throttle PositionLL ON, Idle ON
DFIDirect Fuel Injection (Diesel)Direct Injection (DI)
DIDistributor Ignition±
DLC1
DLC2
DLC3Data Link Connector 1
Data Link Connector 2
Data Link Connector 31: Check Connector
2: Total Diagnosis Comunication Link (TDCL)
3: OBD II Diagnostic Connector
DTCDiagnostic Trouble CodeDiagnostic Code
DTMDiagnostic Test Mode±
ECLEngine Control Level±
ECMEngine Control ModuleEngine ECU (Electronic Control Unit)
ECTEngine Coolant TemperatureCoolant Temperature, Water Temperature (THW)
EEPROMElectrically Erasable Programmable Read Only Memory
Electrically Erasable Programmable Read Only Memory
(EEPROM),
Erasable Programmable Read Only Memory (EPROM)
EFEEarly Fuel EvaporationCold Mixture Heater (CMH), Heat Control Valve (HCV)
EGRExhaust Gas RecirculationExhaust Gas Recirculation (EGR)
EIElectronic IgnitionTOYOTA Distributorless Ignition (TDI)
EMEngine ModificationEngine Modification (EM)
EPROMErasable Programmable Read Only MemoryProgrammable Read Only Memory (PROM)
EVAPEvaporative EmissionEvaporative Emission Control (EVAP)
FCFan Control±
FEEPROMFlash Electrically Erasable Programmable
Read Only Memory±
FEPROMFlash Erasable Programmable Read Only Memory±
FFFlexible Fuel±
FPFuel PumpFuel Pump
GENGeneratorAlternator
GNDGroundGround (GND)