
010B6±13
±
INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS01±21
AVENSIS REPAIR MANUAL (RM1018E)
HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS
GENERAL INFORMATION
There are many ECU controlled systems used in the AVENSIS. In general, ECU controlled system are con-
sidered to be very intricate and require a high level of technical knowledge an\
d expert skill to troubleshoot.
The fact is, however, that if you proceed by inspecting the circuits one by one, troubleshoo\
ting of these sys-
tems is not complex. If you have adequate understanding of the system and ba\
sic knowledge of electricity,
the problem can be accurately diagnosed and fixed. This manual is design\
ed based on the above principle
to help service technicians perform accurate and effective troubleshooting, and is compiled for the following
major ECU controlled systems:
The troubleshooting procedures are described on the following pages.
SystemPage
1. SFI System [1ZZ±FE, 3ZZ±FE]05±1
2. SFI System [1AZ±FE]05±143
3. SFI System [1AZ±FSE]05±290
4. ECD System [1CD±FTV]05±523
5. ABS with EBD System05±696
6. ABS with EBD & BA & TRC & VSC System05±752
7. Electronic Controlled Automatic Transmission [ECT] [U241 (1AZ±FE)]05±856
8. Electronic Controlled Automatic Transmission [ECT] [U241 (1AZ±FSE)]05±915
9. Electronic Controlled Automatic Transmission [ECT] [U341]05±980
10.Electronic Motor Power Steering System05±1042
11. Air Conditioning System05±1088
12.Combustion Type Power Heater System05±1161
13.Supplemental Restraint System05±1181
14.Audio System05±1393
15.Navigation System05±1435
16.Combination Meter05±1497
17.Power Door Lock Control System05±1534
18.Wireless Door Lock Control System05±1568
19.Key Reminder Warning System05±1586
20.Engine Immobiliser System05±1599
21.Theft Deterrent System05±1627
22.Multiplex Communication System05±1654
23.Cruise Control System05±1697
FOR USING HAND±HELD TESTER
Before using the tester, the tester's operator manual should be read thoroughly.
If the tester cannot communicate with the ECU controlled systems when you \
have connected the cable
of tester to the DLC3, turned the ignition switch ON and operated the test\
er, there is a problem on the
vehicle side or tester side.
(1) If the communication is normal when the tester is connected to another veh\
icle, inspect the diag-
nosis data link line (Bus line) or ECU power circuit of the vehicle.
(2) If the communication is still impossible when the tester is connected to a\
nother vehicle, the prob- lem is probably in the tester itself, so perform the Self Test procedures outlined in the Tester Oper-
ator 's Manual.
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D25083
Vibrate Slightly
Shake Slightly
Vibrate
Slightly
D25084
Malfunction
±
INTRODUCTION HOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS01±27
AVENSIS REPAIR MANUAL (RM1018E)
SYMPTOM SIMULATION
HINT:
The most difficult case in troubleshooting is when no symptoms occurs. In such cases\
, a thorough customer
problem analysis must be carried out. Then the same or similar conditions and e\
nvironment in which the
problem occurred in the customer's vehicle should be simulated. No matter how much experience a techni-
cian has, or how skilled he may be, if he proceeds to troubleshoot without c\
onfirming the problem symptoms,
he will tend to overlook something important in the repair operation and make a wrong guess somewhere,
which will only lead to a standstill. For example, for a problem which only o\
ccurs when the engine is cold,
or for a problem which occurs due to vibration caused by the road during d\
riving, etc., the problem can never
be determined when the engine is hot or when the vehicles is at a standsti\
ll. Since vibration, heat or water
penetration (moisture) is a likely cause for the problem which is difficult to reproduce, the symptom simulation
tests introduced here are effective measures in a point that the external causes are applied to the vehicle
in a stationary condition.
Important points in the symptom simulation test:
In the symptom simulation test, the problem symptoms should be confirmed, \
and the problem area or parts
must also be discovered. To do so, reduce the possible problem circuits according to the symptoms before
starting this type of test and have the hand±held tester connected beforehand\
. After that, carry out the symp-
tom simulation test, judging whether the circuit being tested is defective \
or normal and also confirming the
problem symptoms at the same time. Refer to the problem symptoms table of each system to narrow down
the possible causes of the symptom.
1. VIBRATION METHOD: When vibration seems to be
the major cause.
(a) PART AND SENSOR
(1) Apply slight vibration with your finger to the part ofthe sensor considered to be the problem cause and
check whether the malfunction occurs.
HINT:
Applying strong vibration to relays may result in open relays.
(b) CONNECTORS (1) Slightly shake the connector vertically and horizon-tally.
(c) WIRE HARNESS
(1) Slightly shake the wire harness vertically and hori-zontally.
The connector joint and fulcrum of the vibration are
the major areas that should be checked thoroughly.
2. HEAT METHOD: If the problem seems to occur when the area in question is heated.
(a) Heat the component that is the possible cause of the mal- function with a hair dryer or similar object. Check if the
malfunction occurs.
NOTICE:
Do not heat the components to more than 60 C
(140 F) (Temperature is limited to keep the compo-
nents from being damaged).
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022KR±01
±
PREPARATION INTAKE
02±7
AVENSIS REPAIR MANUAL (RM1018E)
INTAKE
PREPARATION
SST
09992±00242Turbocharger Pressure GaugeTURBO CHARGER SYSTEM
(1CD±FTV)
Recomended Tools
09082±00040TOYOTA Electrical TesterTURBO CHARGER SYSTEM
(1CD±FTV)
(09083±00150)Test Lead SetTURBO CHARGER SYSTEM
(1CD±FTV)
Equipment
Vacuum gauge
Voltmeter
Ohmmeter
Service wire harness
Torque wrench
Slide calipers
Radiator cap testor
Vernier calipers
Hand±held vacuum pump
Wooden block
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100EZ±02
A75903
Air
A53763
VG
EVG
10±54
±
ENGINE CONTROL SYSTEMECD SYSTEM(1CD±FTV)
AVENSIS REPAIR MANUAL (RM1018E)
ECD SYSTEM(1CD±FTV)
ON±VEHICLE INSPECTION
1.INSPECTMASS AIR FLOW METER
(a)If you have hand±held tester: Inspect for operation
(1)Connect the hand±held tester to the DLC3.
(2)Turn the ignition switch ON.
(3)Blow air into the MAF meter, and check that the airflow fluctuates (MAF ) of the CURRENT DATA
shown the standard value.
If operation is not as specified, check the MAF meter (See page
10±56), wiring and ECM.
(b)If you have no hand±held tester: Inspect for operation
(1)Turn the ignition switch ON.
(2)Connect the positive tester probe of the voltmeterto the terminal VG of the ECM. and the negative tes-
ter probe of the voltmeter to the terminal EVG of the
ECM.
(3)Blow air into the MAF meter, and check that the volt- age fluctuates.
If operation is not as specified, check the MAF meter (See page
10±56), wiring and ECM.
2.INSPECT INTAKE SHUTTER
(a)Inspect the throttle control motor for operating sound. (1)Turn the ignition switch ON.
(2)When turning the accelerator pedal position sensor lever, check the running sound of the motor.
Also, check that there is no friction sound.
If operation is not as specified, check the throttle control motor (See page 10±56), wiring and ECM.
(b)Inspect the throttle position sensor. (1)Connect the hand±held tester to the DLC3.
(2)Turn the ignition switch ON.
(3)When turning the accelerator pedal position sensor lever to the full±\
open position, check thatthe throttle valve opening percentage (THROTTLE POS) of the CURRENT DATA shown the
standard value.
Standard throttle valve opening percentage:
60 % or more
If operation is not as specified, check that the accelerator pedal positio\
n sensor (See page 10±56), wiring
and ECM.
If you have no hand±held tester, measure voltage between terminals (LU+A ± LU±A, LU+B ± LU±\
B) of the
ECM connector (See page 05±549).
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ENGINE CONTROL SYSTEMECD SYSTEM(1CD±FTV)
10±55
AVENSIS REPAIR MANUAL (RM1018E)
(c)Inspect the air assist system.
(1)Start the engine and check that the CHKENG does not light up.
(2)Allow the engine to warm up to normal operating temperature.
(3)Turn the A/C compressor ON to OFF, and check the idle speed.
Idle speed (Transmission in neutral): 800 50 rpm
NOTICE:
Perform inspection under condition without electrical load.
(d)After checking the above (b) to (d), perform the driving test and check that there is no sense of incon- gruity.
3.INSPECT ACCELERATOR PEDAL POSITION SENSOR
(a)Connect the hand±held tester to the DLC3.
(b)Turn the ignition switch ON.
(c)Check that the voltage (ACCEL POS) of the CURRENT DATA shown the standard value. Accelerator pedal released: 0.5 to 1.1 V
Accelerator pedal depress: 2.6 to 4.5 V
(d)Check that the voltage (ACCEL POS #2) of the CURRENT DATA shown the standard value.
Accelerator pedal released: 1.2 to 2.0 V
Accelerator pedal depress: 3.4 to 5.3 V
If you have no hand±held tester, measure voltage between terminals (VPA1 ± EP1, VPA2 ± EP2) of the ECM
connector (See page 05±549).
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100G6±02
A75903
Air
A79035
VG
EVG
A79035E2
PSW
10±18
±
ENGINE CONTROL SYSTEMSFI SYSTEM(1AZ±FE)
AVENSIS REPAIR MANUAL (RM1018E)
SFI SYSTEM(1AZ±FE)
ON±VEHICLE INSPECTION
1.INSPECTMASS AIR FLOW METER
(a)If you have hand±held tester: Inspect for operation
(1)Connect the hand±held tester to the DLC3.
(2)Turn the ignition switch ON.
(3)Blow air into the MAF meter, and check that the airflow fluctuates (MAF) of the ºDIAGNOSIS / OBD/
MOBD / DATA LIST / ALLº shown the standard val-
ue.
If operation is not as specified, check the MAF meter (See page
10±20), wiring and ECM.
(b)If you have no hand±held tester: Inspect for operation
(1)Turn the ignition switch ON.
(2)Connect the positive tester probe of the voltmeterto the terminal VG of the ECM. and the negative tes-
ter probe of the voltmeter to the terminal EVG of the
ECM.
(3)Blow air into the MAF meter, and check that the volt- age fluctuates.
If operation is not as specified, check the MAF meter (See page
10±20), wiring and ECM.
2. INSPECT POWER STEERING OIL PRESSURE SEN- SOR
(a) Using a voltmeter, measure the voltage between termi-
nals PSW and E2.
Voltage:
ConditionVoltage (V)
Not spin the steering wheel at engine idling9 to 14
Spin the steering wheel at engine idling0 to 3
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100G8±02
A75903
Air
A53763VGEVG
±
ENGINE CONTROL SYSTEMSFI SYSTEM(1AZ±FSE)
10±37
AVENSIS REPAIR MANUAL (RM1018E)
SFI SYSTEM(1AZ±FSE)
ON±VEHICLE INSPECTION
1.INSPECTMASS AIR FLOW METER
(a)If you have hand±held tester:
Inspect for operation
(1)Connect the hand±held tester to the DLC3.
(2)Turn the ignition switch ON.
(3)Blow air into the MAF meter, and check that the airflow fluctuates (MAF ) of the CURRENT DATA
shown the standard value.
If operation is not as specified, check the MAF meter (See page
10±39), wiring and ECM.
(b)If you have no hand±held tester: Inspect for operation
(1)Turn the ignition switch ON.
(2)Connect the positive tester probe of the voltmeterto the terminal VG of the ECM. and the negative tes-
ter probe of the voltmeter to the terminal EVG of the
ECM.
(3)Blow air into the MAF meter, and check that the volt- age fluctuates.
If operation is not as specified, check the MAF meter (See page
10±39), wiring and ECM.
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A53763
E2PSW
10±38
±
ENGINE CONTROL SYSTEMSFI SYSTEM(1AZ±FSE)
AVENSIS REPAIR MANUAL (RM1018E)
2.INSPECT POWER STEERING OIL PRESSURE SEN- SOR
(a)Using a voltmeter, measure the voltage between termi-
nals PSW and E2.
Voltage:
ConditionVoltage (V)
Not spin the steering wheel at engine idling9 to 14
Spin the steering wheel at engine idling0 to 3
3.INSPECT THROTTLE BODY
(a)Inspect the throttle control motor for operating sound.(1)Turn the ignition switch ON.
(2)When turning the accelerator pedal position sensor lever, check the running sound of the motor.Also, check that there is no friction sound.
If operation is not as specified, check the throttle control motor (See page 10±39), wiring and ECM.
(b) Inspect the throttle position sensor.
(1) Connect the hand±held tester to the DLC3.
(2) Turn the ignition switch ON.
(3) When turning the accelerator pedal position sensor lever to the full±\
open position, check thatthe throttle valve opening percentage (THROTTLE POS) of the CURRENT DATA shown the
standard value.
Standard throttle valve opening percentage:
60 % or more
If operation is not as specified, check that the accelerator pedal positio\
n sensor (See page 10±39), wiring
and ECM.
If you have no hand±held tester, measure voltage between terminals (VTA1 ± E2, VTA2 ± E2) of the ECM
connector (See page 05±318).
(c) Inspect the air assist system.
(1) Start the engine and check that the CHK ENG does not light up.
(2) Allow the engine to warm up to normal operating temperature.
(3) Turn the A/C compressor ON to OFF, and check the idle speed.
Idle speed (Transmission in neutral): 700 50 rpm
NOTICE:
Perform inspection under condition without electrical load.
(d) After checking the above (b) to (d), perform the driving test and check that there is no sense of incon-
gruity.
4. INSPECT ACCELERATOR PEDAL POSITION SENSOR
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch ON.
(c) Check that the voltage (ACCEL POS) of the CURRENT DATA shown the standard value.
Accelerator pedal released: 0.5 to 1.1 V
Accelerator pedal depress: 2.6 to 4.5 V
(d) Check that the voltage (ACCEL POS #2) of the CURRENT DATA shown the standard value. Accelerator pedal released: 1.2 to 2.0 V
Accelerator pedal depress: 3.4 to 5.3 V
If you have no hand±held tester, measure voltage between terminals (VPA ± EPA, VPA2 ± EPA2) of the ECM
connector (See page 05±318).
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