2005 TOYOTA AVENSIS ECU

010BA±14
01±42
± INTRODUCTIONTERMS
AVENSIS REPAIR MANUAL (RM1018E)
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/INJ)
DIDistributor Ignition±
DLC1
DLC2
DLC3Data Link Connector 1
Data Link Connector 2
Data Link Connector 31: Check Connector
2: Total Diagnosis Communication Link (TDCL)
3: OBD II Diagnostic Connector
DTCDiagnostic Trouble CodeDiagnostic Trouble 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 IgnitionDistributorless Ignition (DLI)
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)

01±44
± INTRODUCTIONTERMS
AVENSIS REPAIR MANUAL (RM1018E) TCM
Transmission Control ModuleTransmission ECU, ECT ECU
TPThrottle PositionThrottle Position
TRTransmission Range±
TVVThermal Vacuum ValveBimetallic Vacuum Switching Valve (BVSV)
Thermostatic Vacuum Switching Valve (TVSV)
TWCThree±Way Catalytic Converter
Three±Way Catalytic (TWC)
Manifold Converter
CC
RO
TWC+OCThree±Way + Oxidation Catalytic ConverterCCR + CCo
VA FVolume Air FlowAir Flow Meter
VRVoltage RegulatorVoltage Regulator
VSSVehicle Speed SensorVehicle Speed Sensor
WOTWide Open ThrottleFull Throttle
WU±OCWarm Up Oxidation Catalytic Converter±
WU±TWCWarm Up Three±Way Catalytic Converter±
3GRThird Gear±
4GRFourth Gear±

01±38
± INTRODUCTIONTERMS
AVENSIS REPAIR MANUAL (RM1018E)Abbreviations Meaning
DEFDefogger
DFLDeflector
DIFF.Differential
DIFF. LOCKDifferential Lock
D/INJDirect Injection
DLCData Link Connector
DLIDistributorless Ignition
DOHCDouble Overhead Camshaft
DPDash Pot
DSDead Soak
DSPDigital Signal Processor
DTCDiagnostic Trouble Code
DVDDigital Versatile Disc
EBDElectric Brake Force Distribution
ECAMEngine Control And Measurement System
ECDElectronic Controlled Diesel
ECDYEddy Current Dynamometer
ECTElectronic Control Transmission
ECUElectronic Control Unit
EDElectro±Deposited Coating
EDUElectronic Driving Unit
EDICElectric Diesel Injection Control
EFIElectronic Fuel Injection
E/GEngine
EGRExhaust Gas Recirculation
EGR±VMEGR±Vacuum Modulator
ELREmergency Locking Retractor
EMPSElectric Motor Power Steering
ENGEngine
ESAElectronic Spark Advance
ETCS±iElectronic Throttle Control System±intelligent
EVAPEvaporative Emission Control
EVPEvaporator
E±VRVElectric Vacuum Regulating Valve
EXExhaust
FEFuel Economy
FFFront±Engine Front±Wheel±Drive
F/GFuel Gauge
FIPGFormed In Place Gasket
FLFusible Link
F/PFuel Pump
FPUFuel Pressure Up
FrFront
F/WFlywheel
FW/DFlywheel Damper
FWDFront±Wheel±Drive
GASGasoline
GNDGround
GPSGlobal Positioning System
HACHigh Altitude Compensator
H/BHatchback

010B8±08
D25086
WRONG
CORRECT
D25087
Looseness of Crimping
Core Wire
Terminal
Deformation
Pull Lightly 01±32
± INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
AVENSIS REPAIR MANUAL (RM1018E)
ELECTRONIC CIRCUIT INSPECTION PROCEDURE
1. BASIC INSPECTION
(a) RESISTANCE MEASURING CONDITION OF ELECTRONIC PARTS
(1) Unless stated, all resistance is measured at an ambient temperature of 20C (68F). As the re-
sistance may be outside the specifications if measured at high temperatures immediately after
the vehicle has been running, measurements should be made when the engine has cooled
down.
(b) HANDLING OF CONNECTOR
(1) When removing the connector with lock, press the
connector in the direction of the engagement and
remove the lock by lightly pressing the lock claw.
(2) When removing the connector, do not hold the har-
ness, but hold the connector.
(3) Before connecting the connector, check that there
is no deformation, damage or missing terminals.
(4) The connector with a lock should be securely con-
nected until it makes a ºclickº sound.
(5) When checking the connector with a Toyota electri-
cal tester, check it from the backside (harness side)
of the connector using a mini test lead.
NOTICE:

As a water proof connector cannot be checked from
the backside, check by connecting the sub±harness.

Do not damage the terminals by moving the inserted
tester needle.
(c) CONNECTOR CHECKING POINTS
(1) Checking when the connector is connected:
By holding the connector, check the inserted condi-
tion and locking efficiency (engaged condition).
(2) Checking when the connector is removed:
Check by lightly pulling the wire harness (missing
terminal, terminal crimping condition, core wire
break).
Check visually for any rust, metal particles, water
and bent terminals (rust, mixing of foreign object,
terminal deformation).
NOTICE:
When testing a gold±plated female terminal, always use a
gold±plated male terminal.

D25088
Same terminal as
a male terminal
D20024
WRONG
CORRECT
D01557
WRONG
Z17004
C
SensorOPEN
1
2B
1
21
21
2A
Fig. 1
ECU
± INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS01±33
AVENSIS REPAIR MANUAL (RM1018E)
(3) Checking of the contact pressure of the terminal:
Prepare a spare male terminal.
Insert it into a female terminal, check the engaged
condition and sliding resistance.
(d) REPAIR METHOD OF CONNECTOR TERMINAL
(1) If there is on the contact point, clean the contact
point using an air gun or shop rag. However, never
polish the contact point using sand paper as the
platings may come off.
(2) In case of abnormal contact pressure, replace the
female terminal. However, if a male terminal is gold±
plated (gold color), use gold±plated female terminal
and if it is silver±plated (silver color), use silver±
plated female terminal.
(e) HANDLING OF WIRE HARNESS
(1) When removing the wire harness, check the posi-
tioning of the wiring and clamping before starting
work in order to be able to restore it correctly.
(2) Never twist, pull or loosen the wire harness more
than necessary.
(3) Never allow the wire harness to come into contact
with a high±temperature, rotating, moving, vibrating
or sharp (edge of the panel, tip of the screw, etc.)
part.
(4) When installing parts, never let the wire harness be
interfered with.
(5) Never cut or break the cover of the wire harness. If
one is cut or broken, replace it or securely repair it
with electrical tape.
2. CHECK OPEN CIRCUIT
(a) For the open circuit in the wire harness in Fig. 1, perform
a continuity check in step (b) or a voltage check in step (c)
to locate the section.

Z17005
Fig. 2
Sensor
C
BA
ECU
1
21
22 1
B04722
Fig. 3
Sensor
B2
A
1
21
2
21
C
B1
1
2ECU
Z17007
Fig. 4
Sensor
CBA
1
21
2
2 15V
5V
0V 01±34
± INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
AVENSIS REPAIR MANUAL (RM1018E)
(b) Check the continuity.
(1) Disconnect connectors A and C and measure the
resistance between them.
Resistance: 1
or less
HINT:
Measure the resistance while lightly shaking the wire harness
vertically and horizontally.
In the case of Fig. 2:
Between terminal 1 of connector A and terminal 1
of connector C
No continuity (open)
Between terminal 2 of connector A and terminal 2
of connector C
Continuity
Therefore, the cause is an open circuit between ter-
minal 1 of connector A and terminal 1 of connector
C.
(2) Disconnect connector B and measure the resis-
tance between the connectors.
In the case of Fig. 3:
Between terminal 1 of connector A and terminal 1
of connector B1
Continuity
Between terminal 1 of connector B2 and terminal 1
of connector C
No continuity (open)
Therefore, the cause is an open circuit between ter-
minal 1 of connector B2 and terminal 1 of connector
C.
(c) Check the voltage.
(1) In a circuit in which voltage is applied (to the ECU
connector terminal), an open circuit can be checked
by conducting a voltage check.
As shown in Fig. 4, with each connector still con-
nected, measure the voltage between the body
ground and terminal 1 of connector A at the ECU 5
V output terminal, terminal 1 of connector B, and
terminal 1 of connector C, in that order.
(2) If the results are:
5 V: Between terminal 1 of connector A and body
ground
5 V: Between terminal 1 of connector B and body
ground
0 V: Between terminal 1 of connector C and body
ground
Therefore, the cause is an open circuit in the wire
harness between terminal 1 of connector B and ter-
minal 1 of connector C.

Z17008
CSHORT
1
2B
1
21
2 A
Fig. 5
Z17009
Fig. 6
Sensor
C
BA
ECU
1
21
22 1
Z17808
Fig. 7
Sensor
B2
A
11 1
C
B1
1ECU
2
222
± INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS01±35
AVENSIS REPAIR MANUAL (RM1018E)
3. CHECK SHORT CIRCUIT
(a) If the wire harness is ground shorted as shown in Fig. 5,
locate the section by conducting a continuity check with
the body ground in step (b).
(b) Check the continuity with the body ground.
(1) Disconnect connectors A and C and measure the
resistance between terminals 1 and 2 of connector
A and the body ground.
Resistance: 10 k
or higher
HINT:
Measure the resistance while lightly shaking the wire harness
vertically and horizontally.
In the case of Fig. 6:
Between terminal 1 of connector A and body
ground Continuity (short)
Between terminal 2 of connector A and body
ground No continuity
Therefore, the cause is a short circuit between ter-
minal 1 of connector A and terminal 1 of connector
C.
(2) Disconnect connector B and measure the resis-
tance between terminal 1 of connector A and the
body ground, and terminal 1 of connector B2 and
the body ground.
In the case of Fig. 7:
Between terminal 1 of connector A and body
ground No continuity
Between terminal 1 of connector B2 and body
ground Continuity (short)
Therefore, the cause is a short circuit between ter-
minal 1 of connector B2 and terminal 1 of connector
C.

IN0383
Example
Ground
IN0384
Ground ECU Side
W/H Side
Ground
01±36± INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
AVENSIS REPAIR MANUAL (RM1018E)
4. CHECK AND REPLACE ECU
NOTICE:

Start an inspection of the connector from the back-
side of the connector on the wire harness side with
the connector connected to the ECU.

When no measurement condition is specified, per-
form the inspection with the engine stopped and also
the ignition switch ON.
(a) First check the ECU ground circuit. If it is faulty, repair it.
If it is normal, the ECU could be faulty. In this case, re-
place the ECU with one that functions normally and check
if the symptoms appear.
(1) Measure the resistance between the ECU ground
terminal and body ground.
Resistance: 1
or less
(2) Disconnect the ECU connector, check the ground
terminals on the ECU side and wire harness side for
bends and check the contact pressure.