Toyota 1KZ-TE Operating instructions

2000 TOYOTAMOTOR CORPORATION
All rightsreserved. This CD may not be repro-
duced or copied, in whole or in part, without the
written permission of Toyota Motor Corporation.
First Printing: Jun. 28, 2000 01--000628--00
FOREWORD
ThisRepair Manual has been prepared to provide information covering general service repairs for the
1KZ-TE Engine equipped on the TOYOTA HILUX,4RUNNERandLAND CRUISER/ PRADO.
Applicablemodels:KZN165 series (HILUX)
KZN185series(4RUNNER)
KZJ90,KZJ95series(LAND CRUISER/LAND CRUISERPRADO)
Please note that the publications below have also been prepared as relevant service manuals for the
components and system inthisengine.
All information in this manual is based on the latest product information at the time of publication. However,
specifications and procedures are subject to change without notice.
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RM790E-D
1KZ-TE
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TOYOTAMOTOR CORPORATION
CAUTION
This manual does not include all the necessary items about repair and service. This manual is made
for the purpose of the use for the persons who have special techniques and certifications. In the
cases that non--specialized or uncertified technicians perform repair or service only using this manu-
al or without proper equipment or tool, that may cause severe injury to you or other people around
and also cause damage to your customer’s vehicle.
In order to prevent dangerous operation and damages to your customer’s vehicle, be sure to follow
the instruction shown below.
SMust read this manual thoroughly. It is especially important to have good understanding all the
contents written in the PRECAUTION of ”IN” section.
SThe service method written in this manual is very effective to perform repair and service. When
performing the operations following the procedures using this manual, be sure to use toolsspe-
cified and recommended. If using non--specified or recommended tools and service method,
be sure to confirm safety of the technicians and any possibility of causing personal injury or
damage to the customer’s vehicle before starting the operation.
SIf part replacement is necessary, must replace the part with the same part number or equivalent
part. Do not replace it with inferior quality.
SIt is important to note that this manual contains various ”Cautions” and ”Notices” that must be
carefully observed in order to reduce the risk of personal injury during service or repair, or the
possibility that improper service or repair may damage the vehicle or render it unsafe. It is also
important to understand that these ”Cautions” and ”Notices” are not exhaustive, because it is
important to warn of all the possible hazardous consequences that might result from failure to
follow these instructions.
PAGES FROM SUPPLEMENT
S1KZ--T Engine Repair Manual
S1KZ--TE Engine Repair Manual
S1KZ--T, 1KZ--TE Engine Repair Manual Supplement RM522E
RM710E
RM353E
Pub.No.Manual Name

INTRODUCTION
PREPARATION
SERVICE SPECIFICATIONS
DIAGNOSTICS
ENGINE MECHANICAL
TURBOCHARGING
EMISSION CONTROL
ELECTRONIC CONTROL DIESEL
ENGINE FUEL
COOLING
LUBRICATION
STARTING
ALPHABETICAL INDEX
BACK TO MAIN FOREWORD & To Engine Index
Supplement: ENGINE 1KZ-TE: HILUX
MAIN INDEX
DECEMBER 2000
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PAGES FROM SUPPLEMENT1KZ-TE

INTRODUCTION
HOWTOUSETHISMANUALIN--1.............
GENERALINFORMATION IN--1/2..................
IDENTIFICATION INFORMATION IN--3..........
ENGINE SERIALNUMBER IN--3.................
REPAIRINSTRUCTIONS IN--4.................
GENERALINFORMATION IN--4/7..................
FOR ALL OF VEHICLES IN--8..................
PRECAUTION IN--8.............................
HOW TO TROUBLESHOOT ECU
CONTROLLED SYSTEMS IN--9..............
GENERALINFORMATION IN--9..................
HOW TO PROCEED WITH
TROUBLESHOOTING IN-10/19....................
HOW TO USE THE DIAGNOSTIC CHART AND
INSPECTION PROCEDURE IN--20/24...............
TERMSIN--25.................................
ABBREVIATIONS USED INTHISMANUAL IN--25/26....
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PAGES FROM SUPPLEMENT1KZ-TE

IN04V--05
B07996
B08237
N∙m (kgf∙cm, ft∙lbf) : Specified torque
zNon--reusable part
zCrankshaft Front Oil Seal
zGasket
Relief Valve
Spring
Plug
49 (500, 36)
Driven Rotor
--INTRODUCTION HOW TO USE THIS MANUAL
IN--1
1KZ--TE ENGINE SUP (RM790E)
HOW TO USE THIS MANUAL
GENERAL INFORMATION
1. INDEX
An INDEX is provided on the first page of each section to guide you to the item to be repaired. To assist you
in finding your way through the manual, the section title and major heading are given at the top of every page.
2. PRECAUTION
At the beginning of each section, a PRECAUTION is given that pertains to all repair operations contained
in that section.
Read these precautions before starting any repair task.
3. TROUBLESHOOTING
TROUBLESHOOTING tables are included for each system to help you diagnose the problem and find the
cause. The fundamentals of how to proceed with troubleshooting are described on page IN--9.
Be sure to read this before performing troubleshooting.
4. PREPARATION
Preparation lists the SST (Special Service Tools), recommended tools, equipment, lubricant and SSM (Spe-
cial Service Materials) which should be prepared before beginning the operation and explains the purpose
of each one.
5. REPAIR PROCEDURES
Most repair operations begin with an overview illustration. It identifies the components and shows how the
parts fit together.
Example:
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PAGES FROM SUPPLEMENT1KZ-TE
CONTINUED

Illustration:
what to do and where
21. CHECK PISTON STROKE OF OVERDRIVE BRAKE
(a)
Task heading : what to do
SST 09350--30020 (09350--06120)
Set part No. Component part No.
Detailed text : how to do task
(b)
Piston stroke: 1.40 —1.70 mm (0.0551 — 0.0669 in.)
Specification
Place SST and a dial indic ator ont o the ov erdr ive brake pis -
ton as shown in the illus tration.
Measur e the stroke apply ing and releas ing the compressed
air (392— 785 kPa, 4 — 8 kgf/cm
2or 57—114 psi) as shown
in the illus tration.
IN--2
--INTRODUCTION HOW TO USE THIS MANUAL
1KZ--TE ENGINE SUP (RM790E)
The procedur es are presented in a step --by--step format:
SThe illu st ration sh ows what to do and wh ere to do it.
SThe task headi ng tells what to do.
SThe detai led text tells how to perfor m the task and gives other infor mation such as specifications
and warnings .
Example:
This for mat provides the experienced techni cian with a FAST TRACK to the infor mation needed. The upper
casetask headi ng can beread at aglancewhen necessary,and the textbelow itprovides detai led infor ma-
tion. Important spec ifications and warnings alwaysstand out inbold type.
6. REFERENCES
References havebeen kept to aminimum.However,when they arerequired you aregiven the page to refer
to.
7. SPECIFICATIONS
Specifications arepresented inbold typethroughout the textwhere needed. Younever have toleavethe
procedure tolook up your specifications .They arealsofound inServiceSpecifications sectionfor quickref-
erence.
8. CAUTIONS, NOTICES, HINTS:
SCAUTIONS are presentedin boldtype,andindicatethereisapossibility ofinjurytoyouorother
people.
SNOTICESare also presentedin boldtype,andindicatethepossibility ofdamagetothecomponents
being repaired.
SHINTS areseparated from the textbut do not appear inbold. They provideadditional informati on to
help you perform the repairefficiently.
9. SI UNIT
TheUNITSgiven inthismanual areprimarilyexpressed accordingtothe SI UNIT(International System of
Unit),andalternatelyexpresse dinthemetric system andin the English System.
Example:
Torque: 30 N∙m (310 kgf∙cm, 22 ft∙lbf)
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B09246
IN00Q-- 35
--INTRODUCTION IDENTIFICATION INFORMATION
IN--3
1KZ--TE ENGINE SUP (RM790E)
IDENTIFICATION INFORMATION
ENGINE SERIAL NUMBER
The engine serial number is stamped on the engine block as
shown.
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PAGES FROM SUPPLEMENT1KZ-TE

IN0BX-- 12
FI1066
Z11554
Seal lock Adhesive
IN--4
--INTRODUCTION REPAIR INSTRUCTIONS
1KZ--TE ENGINE SUP (RM790E)
REPAIR INSTRUCTIONS
GENERAL INFORMATION
BASIC REPAIR HINT
(a) Use fender, seat and floor covers to keep the vehicle
clean and prevent damage.
(b) During disassembly, keep parts in the appropriate order
to facilitate reassembly.
(c) Observe the following:
(1) Before performing electrical work, disconnect the
negative (--) terminal cable from the battery.
(2) If it is necessary to disconnect the battery for in-
spection or repair, first disconnect the negative (--)
terminal cable.
(3) When disconnecting the terminal cable, to prevent
damage to the battery terminal, loosen the cable
nut and raise the cable straight up without twisting
or prying it.
(4) Clean the battery terminals and cable ends with a
clean shop rag. Do not scrape themwith a file or oth-
er abrasive objects.
(5) Install the cable ends to the battery terminals after
loosening the nut, and tighten the nut after installa-
tion. Do not use a hammer to tap the cable ends
onto the terminals.
(6) Be sure the cover for the positive (+) terminal is
properly in place.
(d) Check hose and wiring connectors to make sure that they
are secure and correct.
(e) Non--reusable parts
(1) Always replace cotter pins, gaskets, O--rings and oil
seals etc. with new ones.
(2) Non--reusable parts are indicated in the component
illustrations by the ”z” symbol.
(f) Precoated parts
Precoated parts are bolts, nuts, etc. that are coated with
a seal lock adhesive at the factory.
(1) If a precoated part is retightened, loosened or
caused to move in any way, it must be recoated with
the specified adhesive.
(2) When reusing precoated parts, clean off the old
adhesive and dry with compressed air. Then apply
the specified seal lock adhesive to the bolt, nut or
threads.
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CONTINUED

BE1367
Medium Current Fuse and High Current Fuse
Equal Amperage Rating
V00076
AbbreviationPart NameSymbolIllustration
FUSE
MEDIUM CURRENT FUSE
HIGH CURRENT FUSE
FUSIBLE LINK
CIRCUIT BREAKER
FUSE
M--FUSE
H--FUSE
FL
CB
--INTRODUCTION REPAIR INSTRUCTIONS
IN--5
1KZ--TE ENGINE SUP (RM790E)
(3) Precoated parts are indicated in the component il-
lustrations by the ”L” symbol.
(g) When necessary, use a sealer on gaskets to prevent
leaks.
(h) Carefully observe all specifications for bolt tightening
torques. Always use a torque wrench.
(i) Use of special service tools (SST) and special service ma-
terials (SSM) may be required, depending on the nature
of the repair. Be sure to use SST and SSM where speci-
fied and follow the proper work procedure. A list of SST
and SSM can be found in Preparation section in this
manual.
(j) When replacing fuses, be sure the new fuse has the cor-
rect amperage rating. DO NOT exceed the rating or use
one with a lower rating.
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CONTINUED

IN0253
WRONG CORRECT
IN0252
WRONG CORRECT
IN--6
--INTRODUCTION REPAIR INSTRUCTIONS
1KZ--TE ENGINE SUP (RM790E)
(k) Care must be taken when jacking up and supporting the
vehicle. Be sure to lift and support the vehicle at the prop-
er locations (As for vehicle lift and support location,
please refer to Chassis & Body Repair Manual for each
vehicle).
SCancel the parking brake on the level place and
shift the transmission in Neutral (or N position).
SWhen jacking up the front wheels of the vehicle at
first place stoppers behind the rear wheels.
SWhen jacking up the rear wheels of the vehicle at
first place stoppers behind the front wheels.
SWhen either the front or rear wheels only should be
jacked up, set rigid racks and place stoppers in front
and behind the other wheels on the ground.
SAfter the vehicle is jacked up, be sure to support it
on rigid racks. It is extremely dangerous to do any
work on a vehicle raised on a jack alone, even for
a small job that can be finished quickly.
(l) Observe the following precautions to avoid damage to the
following parts:
(1) Do not open the cover or case of the ECU unless
absolutely necessary. (If the IC terminals are
touched, the IC may be destroyed by static electric-
ity.)
(2) To disconnect vacuum hoses, pull on the end, not
the middle of the hose.
(3) To pull apart electrical connectors, pull on the con-
nector itself, not the wires.
(4) Be careful not to drop electrical components, such
as sensors or relays. If they are dropped on a hard
floor, they should be replaced and not reused.
(5) When steam cleaning an engine, protect the elec-
tronic components, air filter and emissions--related
components from water.
(6) Never use an impact wrench to remove or install
temperature switches or temperature sensors.
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CONTINUED

IN0002
Example
--INTRODUCTION REPAIR INSTRUCTIONS
IN--7
1KZ--TE ENGINE SUP (RM790E)
(7) When checking continuity at the wire connector, in-
sert the tester probe carefully to prevent terminals
from bending.
(8) When using a vacuum gauge, never force the hose
onto a connector that is too large. Use a step--down
adapter for adjustment. Once the hose has been
stretched, it may leak.
(m) Tag hoses before disconnecting them:
(1) When disconnecting vacuum hoses, use tags to
identify how they should be reconnected.
(2) After completing a job, double check that the vacu-
um hoses are properly connected. A label under the
hood shows the proper layout.
(n) Unless otherwise stated, all resistance is measured at an
ambient temperature of 20˚C(68˚F). Because the resis-
tance may be outside specifications if measured at high
temperatures immediately after the vehicle has been run-
ning, measurement should be made when the engine has
cooled down.
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IN00R-- 14
IN--8
--INTRODUCTION FOR ALL OF VEHICLES
1KZ--TE ENGINE SUP (RM790E)
FOR ALL OF VEHICLES
PRECAUTION
1. FOR VEHICLES EQUIPPED WITH A CATALYTIC CONVERTER
CAUTION:
If large amounts of unburned gasoline flow into the converter, it may overheat and create a fire haz-
ard. To prevent this, observe the following precautions and explain them to your customer.
(a) Use only unleaded gasoline.
(b) Avoid prolonged idling.
Avoid running the engine at idle speed for more than 20 minutes.
(c) Avoid spark jump test.
(1) Perform spark jump test only when absolutely necessary. Perform this test as rapidly as possible.
(2) While testing, never race the engine.
(d) Avoid prolonged engine compression measurement.
Engine compression tests must be done as rapidly as possible.
(e) Do not run engine when fuel tank is nearly empty.
This may cause the engine to misfire and create an extra load on the converter.
(f) Avoid coasting with ignition turned off and prolonged braking.
(g) Do not dispose of used catalyst along with parts contaminated with gasoline or oil.
2. IF VEHICLE IS EQUIPPED WITH MOBILE COMMUNICATION SYSTEM
For vehicles with mobile communication systems such as two--way radios and cellular telephones, observe
the following precautions.
(1) Install the antenna as far as possible away from the ECU and sensors of the vehicle’s electronic
system.
(2) Install the antenna feeder at least 20 cm (7.87 in.) away from the ECU and sensors of the ve-
hicle’s electronics systems. For details about ECU and sensors locations, refer to the section on
the applicable component.
(3) Avoid winding the antenna feeder together with the other wiring, as much as possible, and also
avoid running the antenna feeder parallel with other wire harnesses.
(4) Check that the antenna and feeder are correctly adjusted.
(5) Do not install powerful mobile communications system.
3. FOR USING HAND--HELD TESTER
CAUTION:
Observe the following for safety reasons:
S
SS
SBefore using the hand--held tester, the hand--held tester’s operator manual should be read
throughly.
S
SS
SBe sure to route all cables securely when driving with the hand--held tester connected to the
vehicle. (i.e. Keep cables away from feet, pedals, steering wheel and shift lever.)
S
SS
STwo persons are required when test driving with the hand--held tester, one person to drive the
vehicle and one person to operate the hand--held tester.
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PAGES FROM SUPPLEMENT1KZ-TE

IN005--34
--INTRODUCTION HOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
IN--9
1KZ--TE ENGINE SUP (RM790E)
HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS
GENERAL INFORMATION
A large number of ECU controlled systems are used in the HILUX, 4RUNNER and LAND CRUISER/LAND
CRUISER PRADO. In general, the ECU controlled system is considered to be a very intricate system requir-
ing a high level of technical knowledge and expert skill to troubleshoot. However, the fact is that if you pro-
ceed to inspect the circuits one by one, troubleshooting of these systems is not complex. If you have ade-
quate understanding of the system and a basic knowledge of electricity, accurate diagnosis and necessary
repair can be performed to locate and fix the problem. This manual is designed through emphasis of the
above standpoint to help service technicians perform accurate and effective troubleshooting, and is com-
piled for the following major ECU controlled systems:
The troubleshooting procedure and how to make use of it are described on the following pages.
System Page
Engine DI--1
FOR USING HAND--HELD TESTER
SBefore using the tester, the tester’s operator manual should be read thoroughly.
SIf the tester cannot communicate with ECU controlled systems when you have connected the cable
of the tester to DLC3, turned the ignition switch ON and operated the tester, there is a problem on the
vehicle side or tester side.
(1) If communication is normal when the tester is connected to another vehicle, inspect the diagnosis
data link line (Busline) or ECU power circuit of the vehicle.
(2) If communication is still not possible when the tester is connected to another vehicle, the problem
is probably in the tester itself, so perform the Self Test procedures outline in the Tester Operator’s
Manual.
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IN006--37
Vehicle Brought to Workshop
Customer Problem
Analysis
Symptom Confirmation
and Diagnostic Trouble
Code Check Symptom Simulation
Diagnostic Trouble
Code Chart
Problem Symptoms Table
Circuit Inspection or Parts
Inspection
Repair
Confirmation Test
End
1
2
4
3
5
6
7
8
Ask the customer about the conditions and the
environment when the problem occurred.
1
Confirm the symptoms and the problem condi-
tions, and check the diagnostic trouble codes.
(When the problem symptoms do not appear dur-
ing confirmation, use the symptom simulation
method described later on.)
2, 3
Check the results obtained in Step 2, then confirm
the inspection procedure for the system or the part
which should be checked using the diagnostic
trouble code chart or the problem symptoms table.
4, 5, 6
Check and repair the affected system or part in
accordance with the instructions in Step 6.
7
After completing repairs, confirm that the problem
has been eliminated.
(If the problem is not reproduced, perform the
confirmation test under the same conditions and
in the same environment as when it occurred for
the first time.)
8
IN--10 --INTRODUCTION HOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
1KZ--TE ENGINE SUP (RM790E)
HOW TO PROCEED WITH TROUBLESHOOTING
Carry out troubleshooting in accordance with the procedure on the following page. Here, only the basic pro-
cedure is shown. Details are provided in diagnostics section, showing the most effective methods for each
circuit. Confirm the troubleshooting procedures first for the relevant circuit before beginning troubleshooting
of that circuit.
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CONTINUED

Important Points in the Customer Problem Analysis
DWhat ---------- Vehicle model, system name
DWhen ---------- Date, time, occurrence frequency
DWhere ---------- Road conditions
DUnder what conditions? ---------- Running conditions, driving conditions, weather conditions
DHow did it happen? ---------- Problem symptoms
(Sample) Engine control system check sheet.
ENGINE CONTROL SYSTEM Check Sheet
Customer’s Name
Driver’s Name
Data Vehicle
Brought in
License No.
Model and Model
Year
Frame No.
Engine Model
Odometer Reading km
miles
Problem Symptoms
Engine does
not Start
Difficult to
Start
Poor Idling
Poor
Driveability
Engine Stall
Others
Engine does not crank No initial combustion No complete combustion
Engine cranks slowly
Other
Incorrect first idle Idling rpm is abnormal High ( rpm) Low ( rpm)
Rough idling Other
Hesitation Back fire Muffler explosion (after--fire) Surging
Knocking Other
Soon after starting After accelerator pedal depressed
After accelerator pedal released During A/C operation
Shifting from N to D Other
Datas Problem
Constant Sometimes ( times per day/month)
Inspector’s
Name
CUSTOMER PROBLEM ANALYSIS CHECK
--INTRODUCTION HOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
IN--11
1KZ--TE ENGINE SUP (RM790E)
1. CUSTOMER PROBLEM ANALYSIS
In troubleshooting, the problem symptoms must be confirmed accurately and all preconceptions must be
cleared away in order to give an accurate judgment. To ascertain just what the problem symptoms are, it is
extremely important to ask the customer about the problem and the conditions at the time it occurred.
Important Point in the Problem Analysis:
The following 5 items are important points in the problem analysis. Past problems which are thought to be
unrelated and the repair history, etc. may also help in some cases, so as much information as possible should
be gathered and its relationship with the problem symptoms should be correctly ascertained for reference
in troubleshooting. A customer problem analysis table is provided in the diagnostics section for each system
for your use.
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CONTINUED

DIAGNOSTIC TROUBLE CODE CHECK PROCEDURE
Diagnostic Trouble
Code Check (Make a
note of and then clear)
Confirmation
of Symptoms
Diagnostic Trouble
Code Check Problem Condition
Diagnostic Trouble
Code Display
Problem symptoms
exist
Same diagnostic
trouble code is
displayed
Problem is still occurring in the diagnostic
circuit
Normal code is
displayed
The problem is still occurring in a place
other than in the diagnostic circuit.
(The diagnostic trouble code displayed
first is either for a past problem or it is a
secondary problem.)
No problem
symptoms exist
The problem occurred in the diagnostic
circuit in the past.
Normal Code Display Problem symptoms
exist
Normal code is
displayed
The problem is still occurring in a place
other than in the diagnostic circuit.
No problem
symptoms exist
Normal code is
displayed
The problem occurred in a place other
than in the diagnostic circuit in the past.
IN--12 --INTRODUCTION HOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
1KZ--TE ENGINE SUP (RM790E)
2. SYMPTOM CONFIRMATION AND DIAGNOSTIC TROUBLE CODE CHECK
The diagnostic system in the HILUX, 4RUNNER and LAND CRUISER/LAND CRUISER PRADO fulfills vari-
ous functions. The first function is the Diagnostic Trouble Code Check in which a malfunction in the signal
circuits to the ECU is stored in code in the ECU memory at the time of occurrence, to be output by the techni-
cian during troubleshooting. Another function is the Input Signal Check which checks if the signals from vari-
ous switches are sent to the ECU correctly.
By using these check functions, the problem areas can be narrowed down quickly and troubleshooting can
be performed effectively. Diagnostic functions are incorporated in the following systems in the HILUX, 4RUN-
NER and LAND CRUISER/LAND CRUISER PRADO.
System Diagnostic Trouble
Code Check
Input Signal Check
(Sensor Check)
Other Diagnosis
Function
Engine f
(with Check Mode)
fDiagnostic Test
Mode
In diagnostic trouble code check, it is very important to determine whether the problem indicated by the diag-
nostic trouble code is still occurring or occurred in the past but returned to normal at present. In addition,
it must be checked in the problem symptom check whether the malfunction indicated by the diagnostic
trouble code is directly related to the problem symptom or not. For this reason, the diagnostic trouble codes
should be checked before and after the symptom confirmation to determine the current conditions, as shown
in the table below. If this is not done, it may, depending on the case, result in unnecessary troubleshooting
for normally operating systems, thus making it more difficult to locate the problem, or in repairs not pertinent
to the problem. Therefore, always follow the procedure in correct order and perform the diagnostic trouble
code check.
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CONTINUED

Diagnostic trouble code check
Making a note of and clearing of the diagnostic trouble codes displayed
Symptom confirmation
No problem symptoms
exist
Problem symptoms
exist
Simulation test using the symptom
simulation methods
DNormal code displayed
DProblem symptoms exist
DNormal code displayed
DNo problem symptoms exist
Diagnostic trouble code check
Troubleshooting of problem indicated
by diagnostic trouble code
DDiagnostic trouble code displayed
DProblem symptoms exist
System Normal
Troubleshooting of each
problem symptom If a diagnostic trouble code was
displayed in the initial diagnostic
trouble code check, it indicates
that the trouble may have occurred
in a wire harness or connector in
that circuit in the past. Therefore,
check the wire harness and con-
nectors (See page IN--20).
--INTRODUCTION HOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
IN--13
1KZ--TE ENGINE SUP (RM790E)
Taking into account the points on the previous page, a flow chart showing how to proceed with troubleshoot-
ing using the diagnostic trouble code check is shown below. This flow chart shows how to utilize the diagnos-
tic trouble code check effectively, then by carefully checking the results, indicates how to proceed either to
diagnostic trouble code troubleshooting or to troubleshooting of problem symptoms table.
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CONTINUED

V07268
VIBRATION METHOD: When vibration seems to be the major cause.
CONNECTORS
WIRE HARNESS
PARTS AND SENSOR
1
Slightly shake the connector vertically and horizontally.
Slightly shake the wire harness vertically and horizontally.
The connector joint, fulcrum of the vibration, and body
through portion are the major areas to be checked thorough-
ly.
Apply slight vibration with a finger to the part of the sensor
considered to be the problem cause and check that the
malfunction occurs.
Shake Slightly
Swing Slightly
Vibrate Slightly
HINT:
Applying strong vibration to relays may result in open re-
lays.
IN--14 --INTRODUCTION HOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
1KZ--TE ENGINE SUP (RM790E)
3. SYMPTOM SIMULATION
The most difficult case in troubleshooting is when there are no problem symptoms occurring. In such cases,
a thorough customer problem analysis must be carried out, then simulate the same or similar conditions and
environment in which the problem occurred in the customer’s vehicle. No matter how much experience a
technician has, or how skilled he may be, if he proceeds to troubleshoot without confirming 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 occurs when the en-
gine is cold, or for a problem which occurs due to vibration caused by the road during driving, etc., the prob-
lem can never be determined so long as the symptoms are confirmed with the engine hot condition or the
vehicle at a standstill. Since vibration, heat or water penetration (moisture) is likely to cause for problem
which is difficult to reproduce, the symptom simulation tests introduced here are effective measures in that
the external causes are applied to the vehicle in a stopped condition.
Important Points in the Symptom Simulation Test:
In the symptom simulation test, the problem symptoms should of course be confirmed, but the problem area
or parts must also be found out. To do this, narrow down the possible problem circuits according to the symp-
toms before starting this test and connect a tester beforehand. After that, carry out the symptom simulation
test, judging whether the circuit being tested is defective or normal and also confirming the problem symp-
toms at the same time. Refer to the problem symptoms table for each system to narrow down the possible
causes of the symptom.
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B02389
B02390
HEAT METHOD: When the problem seems to occur when the suspect area is heated.2
NOTICE:
3 WATER SPRINKLING METHOD:
(1)
(2)
4 OTHER: When a malfunction seems to occur when electrical load is excessive.
When the malfunction seems to occur on a rainy day or in a
high--humidity condition.
Heat the component that is the likely cause of the malfunction
with a hair dryer or similar object. Check to see if the malfunction
occurs.
Sprinkle water onto the vehicle and check to see if the malfunc-
tion occurs.
Turn on all electrical loads including the heater blower, head
lights, rear window defogger, etc. and check to see if the mal-
function occurs.
ON
HINT:
If a vehicle is subject to water leakage, the leaked water may
contaminate the ECU. When testing a vehicle with a water leak-
age problem, special caution must be taken.
Malfunc-
tion
Do not heat to more than 60˚C (140˚F). (Temperature
is limited not to damage the components.)
Do not apply heat directly to parts in the ECU.
(1)
(2)
Never sprinkle water directly into the engine compart-
ment, but indirectly change the temperature and hu-
midity by applying water spray onto the radiator front
surface.
Never apply water directly onto the electronic compo-
nents.
NOTICE:
--INTRODUCTION HOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
IN--15
1KZ--TE ENGINE SUP (RM790E)
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DTC No.
Indicates the diagnostic trouble code.
Detection Item
Indicates the system of the problem or
contents of the problem.
Trouble Area
Indicates the suspect area of the
problem.
Vacuum Sensor Circuit Malfunction
Detection Item
DOpen or short in vacuum sensor circuit
DVacuum sensor
DEngine ECU
DTC No.
(See page) Trouble Area
CHK ENG
*Memory
(DI--12)
Intake Air Temp. Circuit Malfunction
DOpen or short in water temp. sensor circuit
DWater temp. sensor
DEngine ECU
Water Temp. Circuit Malfunction
DOpen or short in Oxygen sensor circuit
DOxygen sensor
Throttle Position Sensor Circuit
Malfunction
HINT:
Parameters listed in the chart may not be exactly the same as your reading due to the type of instrument or other
factors.
If a malfunction code is displayed during the DTC check in check mode, check the circuit for the code listed
in the table below. For details of each code, turn to the page referred to under the ”See page” for the respective
”DTC No.” in the DTC chart.
DOpen or short in intake air temp. sensor circuit
DIntake air temp. sensor
DEngine ECU
DOpen or short in throttle position sensor circuit
DThrottle position sensor
DEngine ECU
P0105/31
(DI--28)
P0110/24
(DI--31)
P0115/22
(DI--32)
P0120/41
--
--
*1
DIAGNOSTIC TROUBLE CODE CHART
D
Page or Instructions
Indicates the page where the inspection proce-
dure for each circuit is to be found, or gives
instructions for checking and repairs.
DD
D
IN--16 --INTRODUCTION HOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
1KZ--TE ENGINE SUP (RM790E)
4. DIAGNOSTIC TROUBLE CODE CHART
The inspection procedure is shown in the table below. This table permits efficient and accurate troubleshoot-
ing using the diagnostic trouble codes displayed in the diagnostic trouble code check. Proceed with trouble-
shooting in accordance with the inspection procedure given in the diagnostic chart corresponding to the
diagnostic trouble codes displayed. The engine diagnostic trouble code chart is shown below as an example.
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--INTRODUCTION HOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
IN--17
1KZ--TE ENGINE SUP (RM790E)
5. PROBLEM SYMPTOMS TABLE
The suspected circuits or parts for each problem symptom are shown in the table below. Use this table to
troubleshoot the problem when a ”Normal” code is displayed in the diagnostic trouble code check but the
problem is still occurring. Numbers in the table indicate the inspection order in which the circuits or parts
should be checked.
HINT:
When the problem is not detected by the diagnostic system even though the problem symptom is present,
it is considered that the problem is occurring outside the detection range of the diagnostic system, or that
the problem is occurring in a system other than the diagnostic system.
Symptom Suspected Area See page
Engine does not crank (Does not start)
No initial combustion (Does not start)
No complete combustion (Does not start)
1. Starter and starter relay
1. Engine ECU power source circuit
2. Fuel pump control circuit
3. Engine ECU
1. Starter signal circuit
2. Fuel pump control circuit
1. Fuel pump control circuit
ST--12, 13
DI--124
DI--127
IN--30
PROBLEM SYMPTOMS TABLE
1. Compression
2. Fuel pump control circuit
1. A/C signal circuit
2. Fuel pump control circuit
1. A/C signal circuit (Compressor circuit)
2. Engine ECU power source circuit
1. Starter signal circuit
2. Fuel pump control circuit
1. Starter signal circuit
2. Fuel pump control circuit
3. Compression
idling)
High engine idle speed (Poor idling)
Hot engine
Cold engine (Difficult to start)
Engine cranks normally (Difficult to start)
AC--54
DI--124
DI--121
DI--127
DI--121
DI--127
EM--3
DI--127
DI--121
DI--127
DProblem Symptom
Page
Indicates the page where the flow chart for each circuit
is located.
Circuit Inspection, Inspection Order
Indicates the circuit which needs to be checked for each problem
symptom. Check in the order indicated by the numbers.
Circuit or Part Name
Indicates the circuit or part which needs to be checked.
D
D
D
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