engine repair TOYOTA T100 1996 Factory User Guide
Page 18 of 2062
Downloaded from www.Manualslib.com manuals search engine IN02I−02
− INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMSIN−15
15 Author: Date:
1996 TOYOTA T100 (RM449U)
HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS
GENERAL INFORMATION
A large number of ECU controlled systems are used in the TOYOTA T100. In general, the ECU controlled
system is considered to be a very intricate system requiring a high level of technical knowledge and expert
skill to troubleshoot. However, the fact is that if you proceed to inspect the circuits one by one, troubleshoot-
ing of these systems is not complex. If you have adequate understanding of the system and a basic knowl-
edge 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 ac-
curate and effective troubleshooting, and is compiled for the following major ECU controlled systems:
SystemPage
1. 3RZ−FE EngineDI−1
2. 5VZ−FE EngineDI−127
3. Automatic TransmissionDI−263
4. Anti−Lock Brake systemDI−319
5. Supplemental Restraint SystemDI−363
6. Cruise ControlDI−408
The troubleshooting procedure and how to make use of it are described on the above pages.
Page 19 of 2062
Downloaded from www.Manualslib.com manuals search engine IN02J−03
Vehicle Brought Workshop
Customer Problem
Analysis
Symptom Confirmation
and Diagnostic Trouble
Code Check
Symptom Simulation
Diagnostic Trouble
Code Chart
Matrix Chart of Problem
Symptoms
Circuit Inspection or Parts
Inspection
Repair
Confirmation Test
End 1
2
43
5
6
7
8Ask the customer about the conditions and the
environment when the problem occurred.1
Confirm the symptoms and the problem conditions,
and check the diagnostic trouble codes.
(When the problem symptoms do not appear
during 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 matrix chart of problem
symptoms.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−16− INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
1996 TOYOTA T100 (RM449U)
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 each section, showing the most effective methods for each circuit.
Confirm the troubleshooting procedures first for the relevant circuit before beginning troubleshooting of that
circuit.
Page 20 of 2062
Downloaded from www.Manualslib.com manuals search engine Important Points in the Customer Problem Analysis
What −−−−− Vehicle model, system name
When −−−−− Date, time, occurrence frequency
Where −−−−− Road conditions
Under what conditions? −−−−− Running conditions, driving conditions, weather conditions
How 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
Drive ability
Engine Stall
Others
Engine does not crankNo initial combustionNo complete combustion
Engine cranks slowly
Other
Incorrect first idleIdling rpm is abnormalHigh ( rpm)Low ( rpm)
Rough idling
Other
HesitationBack fireMuffler explosion (after−fire)Surging
Knocking
Other
Soon after startingAfter accelerator pedal depressed
After accelerator pedal released
During A/C operation
Shifting from N to D
Other
Datas Problem
ConstantSometimes ( times per day/month)
Inspector’s
Name
CUSTOMER PROBLEM ANALYSIS CHECK
− INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMSIN−17
1996 TOYOTA T100 (RM449U)
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 judgement. 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 troubleshooting section for each
system for your use.
Page 21 of 2062
Downloaded from www.Manualslib.com manuals search engine DIAGNOSTIC TROUBLE CODE CHECK PROCEDURE
Diagnostic Trouble
Code Check (Make a
note of and then clear)Confirmation
of SymptomsDiagnostic Trouble
Code CheckProblem Condition
Diagnostic Trouble
Code DisplayProblem symptoms
existSame diagnostic
trouble code is
displayedProblem is still occurring in the diagnostic
circuit.
Normal code is
displayedThe 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 existThe problem occurred in the diagnostic
circuit in the past.
Normal Code DisplayProblem symptoms
existNormal code is
displayedThe problem is still occurring in a place
other than in the diagnostic circuit.
No problem
symptoms existNormal code is
displayedThe problem occurred in a place other
than in the diagnostic circuit in the past.
IN−18− INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
1996 TOYOTA T100 (RM449U)
2. SYMPTOM CONFIRMATION AND DIAGNOSTIC TROUBLE CODE CHECK
The diagnostic system in the TOYOTA T100 fulfills various 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 technician during troubleshooting. Another function
is the Input Signal Check which checks if the signals from various 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 TOYOTA
T100.
SystemDiagnostic Trouble
Code CheckInput Signal Check
(Sensor Check)Other Diagnosis
Function
Engine (3RZ−FE, 5VZ−FE)
Automatic Transmission
Anti−Lock Brake system
Supplemental Restraint System
Cruise Control (with Test Mode)
(with Test Mode)
Cancel Signal
Check
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.
Page 23 of 2062
Downloaded from www.Manualslib.com manuals search engine V07268
VIBRATION METHOD: When vibration seems to be the major cause.
CONNECTORS
WIRE HARNESS
PARTS AND SENSOR1
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 if the
malfunction occurs.Shake Slightly
Swing Slightly
Vibrate Slightly
HINT: Applying strong vibration to relays may result in open
relays. IN−20
− INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
1996 TOYOTA T100 (RM449U)
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 cause for problem which
is difficult to reproduce, the symptom simulation tests introduced here are effective measures in that the ex-
ternal 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 matrix chart of problem symptoms for each system to narrow down the
possible causes of the symptom.
Page 25 of 2062
Downloaded from www.Manualslib.com manuals search engine DTC No.
Indicates the diagnostic trouble code.
Page or Instructions
Indicates the page where the inspection procedure
for each circuit is to be found, or gives instructions
for checking and repairs.
Detection Item
Indicates the system of the problem or
contents of the problem. Trouble Area
Indicates the suspect area of the
problem.
Mass Air Flow Circuit MalfunctionDetection Item
Open or short in mass air flow meter circuit
Mass air flow meter
ECM DTC No.
(See page)Trouble AreaMIL*MemoryP0100
(DI − 26)
P0101
(DI − 31)Mass Air Flow Circuit
Range/Performance Problem Mass air flow meter
P0115
(DI − 37) Open or short in intake air temp. sensor circuit
Intake air temp. sensor
ECM Intake Air Temp. Circuit Malfunction P0110
(DI − 32)
Engine Coolant Temp. Circuit
Range/Performance Problem Open or short in engine coolant temp. sensor circuit
Engine coolant temp. sensor
ECM
P0120
(DI − 43)
Throttle/ Pedal Position Sensor/Switch
”A” Circuit Range/Performance
P0116
(DI − 41)
Throttle/Pedal Position Sensor/Switch
”A” Circuit Malfunction
Insufficient Coolant Temp. for Closed Engine coolant temp. sensor
Cooling system Engine Coolant Temp. Circuit
Malfunction
Open or short in throttle position sensor circuit
Throttle position sensor
ECM
Throttle position sensor
Open or short in heated oxygen sensor circuit
Heated oxygen sensor
DTC CHART (SAE Controlled)
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 mode, check the circuit for that 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.
IN−22− INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
1996 TOYOTA T100 (RM449U)
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.
Page 33 of 2062
Downloaded from www.Manualslib.com manuals search engine Z17808
Fig. 7
SensorECU
C
A
1
21
21
221 B2 B1
IN0383
Example
Ground
IN0384
ECU Side
Ground
W/H Side
Ground
IN−30− INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
1996 TOYOTA T100 (RM449U)
(2) Disconnect connector ”B” and measure the resis-
tance between terminal 1 of connector ”A” and body
ground, and terminal 1 of connector ”B2” and body
ground.
Between terminal 1 of connector ”A” and body
ground → No continuity
Between terminal 1 of connector ”B2” and body
ground → Continuity (short)
Therefore, it is found out that there is a short circuit
between terminal 1 of connector ”B2” and terminal
1 of connector ”C”.
8. CHECK AND REPLACE ECU
First check the ECU ground circuit. If it is faulty, repair it. If it is
normal, the ECU could be faulty, so replace the ECU with a nor-
mal functioning one and check that the symptoms appear.
(1) Measure the resistance between the ECU ground
terminal and the body ground.
Resistance: 1 Ω or less
(2) Disconnect the ECU connector, check the ground
terminals on the ECU side and the wire harness
side for bend and check the contact pressure.
Page 47 of 2062
Downloaded from www.Manualslib.com manuals search engine B02088
MA015−02
B02089
B02090
MA−8
− MAINTENANCECHASSIS
43 Author: Date:
1996 TOYOTA T100 (RM449U)
CHASSIS
INSPECTION
1. INSPECT STEERING LINKAGE
(a) Check the steering wheel freeplay (See page SR−9).
(b) Check the steering linkage for looseness or damage.
Check that:
Tie rod ends and relay rod ends do not have exces-
sive play.
Dust seals are not damaged.
2WD:
Boot clamps are not loose.
2. INSPECT SRS AIRBAG (See page RS−2)
3. INSPECT STEERING GEAR HOUSING OIL
Check the steering gear housing for oil leaks.
If leakage is found, check for cause and repair.
4. 4WD:
INSPECT DRIVE SHAFT BOOTS
Inspect the drive shaft boots for clamp looseness, grease leak-
age or damage.
5. INSPECT BALL JOINTS AND DUST COVERS
(a) Inspect the ball joints for excessive looseness.
(b) Inspect the dust cover for damage.
Page 189 of 2062
Downloaded from www.Manualslib.com manuals search engine SS00O−07
− SERVICE SPECIFICATIONSENGINE MECHANICAL (5VZ−FE)
SS−9
183 Author: Date:
1996 TOYOTA T100 (RM449U)
ENGINE MECHANICAL (5VZ−FE)
SERVICE DATA
Compression
pressureat 250 rpm STD
Minimum
Difference of pressure between each cylinder1,200 kPa (12.2 kgf/cm2, 174 psi)
1,000 kPa (10.2 kgf/cm2, 145 psi)
100 kPa (1.0 kgf/cm2, 15 psi) or less
Valve
clearanceat cold Intake
Exhaust
Adjusting shim for repair part Mark 2.500
Mark 2.550
Mark 2.600
Mark 2.650
Mark 2.700
Mark 2.750
Mark 2.800
Mark 2.850
Mark 2.900
Mark 2.950
Mark 3.000
Mark 3.050
Mark 3.100
Mark 3.150
Mark 3.200
Mark 3.250
Mark 3.3000.13 − 0.23 mm (0.006 − 0.009 in.)
0.27 − 0.37 mm (0.011 − 0.014 in.)
2.500 mm (0.0984 in.)
2.550 mm (0.1004 in.)
2.600 mm (0.1024 in.)
2.650 mm (0.1043 in.)
2.700 mm (0.1063 in.)
2.750 mm (0.1083 in.)
2.800 mm (0.1102 in.)
2.850 mm (0.1122 in.)
2.900 mm (0.1142 in.)
2.950 mm (0.1161 in.)
3.000 mm (0.1181 in.)
3.050 mm (0.1201 in.)
3.100 mm (0.1220 in.)
3.150 mm (0.1240 in.)
3.200 mm (0.1260 in.)
3.250 mm (0.1280 in.)
3.300 mm (0.1299 in.)
Ignition timingw/ Terminals TE1 and E1 connected of DLC18 − 12° BTDC @ idle
Idle speed−700 ± 50 rpm
Intake manifold
vacuumat idle speed60 kPa (450 mmHg, 17.7 in.Hg) or more
Timing belt
tensionerProtrusion from housing side10.0 − 10.8 mm (0.394 − 0.425 in.)
Cylinder headWarpage Maximum
Valve seat
Refacing angle
Contacting angle
Contacting width
Valve guide bushing bore diameter STD
O/S 0.050.10 mm (0.039 in.)
30°, 45°, 60°
45°
1.0 − 1.4 mm (0.039 − 0.055 in.)
10.985 − 11.027 mm (0.4325 − 0.4341 in.)
11.050 − 11.077 mm (0.4350 − 0.4361 in.)
Valve guide
bushingInside diameter
Outside diameter for repair part STD
O/S 0.056.010 − 6.030 mm (0.2366 − 0.2374 in.)
11.033 − 11.044 mm (0.4344 − 0.4348 in.)
11.083 − 11.094 mm (0.4363 − 0.4368 in.)
ValveValve overall length STD Intake
Exhaust
Minimum Intake
Exhaust
Valve face angle
Stem diameterIntake
Exhaust
Stem oil clearance STD Intake
Exhaust
Maximum Intake
Exhaust
Margin thickness STD
Minimum95.15 mm (3.7461 in.)
94.90 mm (3.7362 in.)
94.60 mm (3.7244 in.)
94.40 mm (3.7165 in.)
44.5°
5.970 − 5.985 mm (0.2350 − 0.2356 in.)
5.965 − 5.980 mm (0.2348 − 0.2354 in.)
0.025 − 0.060 mm (0.0010 − 0.0024 in.)
0.030 − 0.065 mm (0.0012 − 0.0026 in.)
0.08 mm (0.0031 in.)
0.10 mm (0.0039 in.)
1.0 mm (0.039 in.)
0.5 mm (0.020 in.)
Page 265 of 2062
Downloaded from www.Manualslib.com manuals search engine DI0T5−02
Vehicle Brought to Workshop
Customer Problem Analysis P. DI−2
Problem Symptom Confirmation
If the engine does not start perform steps 10 and 12 firstConnect the OBD II scan tool or TOYOTA hand−held tester to DLC3 P. DI−3
If the display indicates a communication fault in the tool, inspect DLC3 P. DI−3
Check DTC and Freezed Frame Data (Precheck)
Record or Print DTC and Freezed Frame Data P. DI−3
Clear DTC and Freezed Frame Data P. DI−3
Visual Inspection
Setting the Check Mode Diagnosis P. DI−3
Symptom Simulation P.IN−16
Basic Inspection P. DI−3DTC Chart P. DI−13
Problem Symptoms Table P. DI−21
Circuit Inspection P. DI−22
Adjustment, Repair
DTC Check P. DI−3
Titles insideare titles of pages in
in the bottom portion. See the indicated
pages for detailed explanations.this manual with the page number indicated
Malfunction
occurs.Malfunction does not occur.
Parts Inspection
Check for Intermittent Problems P. DI−3
Identification of Problem
Confirmation Test
End 1
2
3
4
5
6
7
108
9
11
12
13
15 14
16
Normal Malfunction code.
17
− DIAGNOSTICSENGINE (3RZ−FE)
DI−1
258 Author: Date:
1996 TOYOTA T100 (RM449U)
ENGINE (3RZ−FE)
HOW TO PROCEED WITH TROUBLESHOOTING
Troubleshoot in accordance with the procedure on the following page.