TOYOTA LAND CRUISER 1998 Factory Repair Manual

A19522A19630
IGT2
IGT3 IGT4
IGT6IGT8
IGT1
IGT7 IGT5(+) (+) (+)
(+) (+)
(+)
(+) (+)
ECM Connector
E7E1 (-)E5
DI-212
- DIAGNOSTICSENGINE
405 Author
: Date
:
2004 LAND CRUISER (RM1071U)
6 Disconnect ignition coil with igniter connector, and check voltage between ter-
minals IGT1 - IGT8 of ECM connector and body ground.
PREPARATION:
Disconnect the I1, I2, I3, I4, I5, I6, I7 or I8 ignition coil with igniter
connector.
CHECK:
Measure the voltage between terminals the E5 and E7 ECM
connectors when the engine is cranked.
OK:
Tester ConnectionSpecified Condition
IGT1 (E5-9) - E1 (E7-1)
IGT2 (E5-8) - E1 (E7-1)
IGT3 (E5-25) - E1 (E7-1)
IGT4 (E5-11) - E1 (E7-1)45VIGT5 (E5-12) - E1 (E7-1)4.5 V or more
IGT6 (E5-26) - E1 (E7-1)
IGT7 (E5-13) - E1 (E7-1)
IGT8 (E5-10) - E1 (E7-1)
NG Replace ECM (See page SF-60).
OK

A21025
Wire Harness Side:
I1
I2
I3I4
I5I6
I7I8Ignition Coil with
Igniter Connector
- DIAGNOSTICSENGINE
DI-213
406 Author
: Date
:
2004 LAND CRUISER (RM1071U)
7 Check ignition coil with igniter power source circuit.
PREPARATION:
Disconnect the I1, I2, I3, I4, I5, I6, I7 or I8 ignition coil with igniter
connector.
CHECK:
Measure the voltage between the terminal of the wire harness
side connector and body ground.
OK:
Tester ConnectionSpecified Condition
I1-1 - Body ground
I2-1 - Body ground
I3-1 - Body ground
I4-1 - Body ground9t 14VI5-1 - Body ground9 to 14 V
I6-1 - Body ground
I7-1 - Body ground
I8-1 - Body ground
OK Repair ignition coil with igniter.
NG

A21025
Wire Harness Side:
I1
I2
I3I4
I5I6
I7I8Ignition Coil with Igniter
1 234
5 678
A21030
Wire Harness Side:
I18
Ignition SwitchIG2
DI-214
- DIAGNOSTICSENGINE
407 Author
: Date
:
2004 LAND CRUISER (RM1071U)
8 Check for open and short in harness and connector between ignition switch and
ignition coil with igniter.
PREPARATION:
(a) Disconnect the I1, 2, I3, I4, I5, I6, I7 or I8 ignition coil with
igniter connector.
(b) Disconnect the I18 ignition switch connector.
CHECK:
Measure the resistance between the wire harness side connec-
tors.
OK:
Tester ConnectionSpecified Condition
Ignition coil (I1-1) - IG2 (I18-6)Below 1 W
Ignition coil (I2-1) - IG2 (I18-6)Below 1 W
Ignition coil (I3-1) - IG2 (I18-6)Below 1 W
Ignition coil (I4-1) - IG2 (I18-6)Below 1 W
Ignition coil (I5-1) - IG2 (I18-6)Below 1 W
Ignition coil (I6-1) - IG2 (I18-6)Below 1 W
Ignition coil (I7-1) - IG2 (I18-6)Below 1 W
Ignition coil (I8-1) - IG2 (I18-6)Below 1 W
Ignition coil (I1-1) or IG2 (I18-6) -
Body ground10 kW or higher
Ignition coil (I2-1) or IG2 (I18-6) -
Body ground10 kW or higher
Ignition coil (I3-1) or IG2 (I18-6) -
Body ground10 kW or higher
Ignition coil (I4-1) or IG2 (I18-6) -
Body ground10 kW or higher
Ignition coil (I5-1) or IG2 (I18-6) -
Body ground10 kW or higher
Ignition coil (I6-1) or IG2 (I18-6) -
Body ground10 kW or higher
Ignition coil (I7-1) or IG2 (I18-6) -
Body ground10 kW or higher
Ignition coil (I8-1) or IG2 (I18-6) -
Body ground10 kW or higher
NG Repair or replace harness or connector.
OK
Replace ignition coil with igniter.

A20596
Normal Catalyst
Abnormal Catalyst Waveform of
Heated Oxygen Sensor
(before Catalyst) Waveform of
Heated Oxygen Sensor
(before Catalyst)
Waveform of
Heated Oxygen Sensor
(after Catalyst) Waveform of
Heated Oxygen Sensor
(after Catalyst)
- DIAGNOSTICSENGINE
DI-215
408 Author
: Date
:
DTC P0420 Catalyst System Efficiency Below Threshold
(Bank 1)
DTC P0430 Catalyst System Efficiency Below Threshold
(Bank 2)
MONITOR DESCRIPTION
The vehicle is equipped with two heated oxygen sensors. One is mounted upstream from the TWC (Three-
Way Catalytic) converter (Front Oxygen Sensor, ºsensor 1º), the second is mounted downstream (Rear Oxy-
gen Sensor ºsensor 2º). The catalyst efficiency monitor compares the sensor 1 and sensor 2 signals in order
to calculate TWC ability to store the oxygen.
During normal operation, the TWC stores and releases oxygen as needed. This results in low oxygen varia-
tions in the post TWC exhaust stream as shown below.
DIC2G-01

A20598
Signal Length
Heated Oxygen Sensor Signal Length
Sensor Output
Voltage
Time DI-216
- DIAGNOSTICSENGINE
409 Author
: Date
:
DTC No.DTC Detecting ConditionTrouble Area
P0420
P0430
After engine and catalyst are warmed up, and while vehicle is
driven within set vehicle and engine speed range, waveform of
heated oxygen sensors have same amplitude
(2 trip detection logic)
Gas leakage on exhaust system

Heated oxygen sensor (bank 1, 2 sensor 1, 2)

Three-way catalytic converter
HINT:

Bank 1 refers to the bank that includes cylinder No.1.

Bank 2 refers to the bank that does not include cylinder No.1.

Sensor 1 refers to the sensor closest to the engine assembly.

Sensor 2 refers to the sensor farthest away from the engine assembly.
MONITOR STRATEGY
RltdDTCP0420Bank 1 catalyst is deterioratedRelated DTCsP0430Bank 2 catalyst is deteriorated
Main sensors/componentsFront and rear heated oxygen sensor
Required sensors/componentsRelated sensors/components
Mass air flow meter, Engine coolant temperature
sensor, Engine speed sensor, Intake air tempera-
ture sensor
Frequency of operationOnce per driving cycle
Duration90 sec.
MIL operation2 driving cycles
Sequence of operationNone

- DIAGNOSTICSENGINE
DI-217
410 Author
: Date
:
TYPICAL ENABLING CONDITIONS
ItSpecificationItemMinimumMaximum
The monitor will run whenever the follow-
ing DTCs are not presentSee ºList of disable a monitorº (on page DI-3)
Battery voltage11 V-
Intake air temperature-10C (14F)-
IdleOFF
Intake air amount8 g/sec.50 g/sec.
Engine speed-4,000 rpm
Engine coolant temperature75°C (167°F)
Estimated catalyst temperature conditions
are met:A and B
A. Estimated temperature of up stream
catalyst450C (842F)820C (1,508F)
B. Estimated temperature of down stream
catalyst450C (842F)820C (1,508F)
Fuel system statusClosed loop
TYPICAL MALFUNCTION THRESHOLDS
Detection CriteriaThreshold
Catalyst deterioration level (Heated oxygen sensor locus
length ratio)0.6 or more
Number of times detection8 times
MONITOR RESULT
The detailed information is described in CHECKING MONITOR STATUSº (see page DI-3).

TID (Test Identification) is assigned to each emission-related component.

TLT (Test Limit Type):
If TLT is 0, the component is malfunctioning when the test value is higher than the test limit.
If TLT is 1, the component is malfunctioning when the test value is lower than the test limit.

CID (Component Identification) is assigned to each test value.

Unit Conversion is used to calculate the test value indicated on generic OBD scan tools.
TID $01: Catalyst- Using Front HO2S and Rear HO2S
TLTCIDUnit ConversionDescription of Test ValueDescription of Test Limit
0$01Multiply by 0.0078
(no dimension)Catalyst deterioration level bank 1:
Determined by waveform of front HO2S and rear HO2SMalfunction criterion
0$02Multiply by 0.0078
(no dimension)Catalyst deterioration level bank 2:
Determined by waveform of front HO2S and rear HO2SMalfunction criterion

FI7132
Engine Speed
2,500 - 3,000 rpm
Idling
IG SW OFF(1)
Time Warmed up 3 min. or so Check (2)(3)
(4)
FI6514
OX Signal Waveform (Oscilloscope)
1.0 V
0 V
200 msec./Division DI-218
- DIAGNOSTICSENGINE
411 Author
: Date
:
CONFIRMATION ENGINE RACING PATTERN
(a) Connect the hand-held tester to the DLC3, or connect the probe of the oscilloscope between terminals
OXL1, OXL2, OXR1, OXR2 and E1 of the ECM connector.
(b) Start the engine and warm it up with all accessories switched OFF until engine coolant temperature
is stable.
(c) Race the engine at 2,500 - 3,000 rpm for about 3 minutes.
(d) After confirming that the waveform of the heated oxygen sensor (bank 1, 2 sensor 1 (OX1A, OX2A)),
oscillate around 0.5 V during feedback to the ECM, check the waveform of the heated oxygen sensor
(bank 1, 2 sensor 2 (OX1B, OX2B)).
HINT:
If there is a malfunction in the system, the waveform of the
heated oxygen sensor (bank 1, 2 sensor 2 (OX1B, OX2B)) is
almost the same as that of the heated oxygen sensor (bank 1,
2 sensor 1 (OX1A, OX2A)) on the left.
There are some cases where, even though a malfunction ex-
ists, the MIL may either light up or not light up.

- DIAGNOSTICSENGINE
DI-219
412 Author
: Date
:
INSPECTION PROCEDURE
HINT:
Read freeze frame data using the hand-held tester or the OBD II scan tool. Freeze frame data records the
engine conditions when a malfunction is detected. When troubleshooting, freeze frame data can help deter-
mine if the vehicle was running or stopped, if the engine was warmed up or not, if the air-fuel ratio was lean
or rich, as well as other data from the time when a malfunction occurred.
1 Are there any other codes (besides DTC P0420 or P0430) being output?
PREPARATION:
(a) Connect the hand-held tester or the OBD II scan tool to the DLC3.
(b) Turn the ignition switch ON and push the hand-held tester or OBD II scan tool main switch ON.
(c) When using hand-held tester, enter the following menus: DIAGNOSIS / ENHANCED OBD II / DTC
INFO / CURRENT CODES.
CHECK:
Read the DTC using the hand-held tester or the OBD II scan tool.
RESULT:
Display (DTC Output)Proceed to
ºP0420 and/or P0430ºA
ºP0420 or P0430º and other DTCsB
HINT:
If any other codes besides ºP0420 and/or P0430º are output, perform the troubleshooting for those DTCs
first.
B Go to relevant DTC chart (See page DI-36).
A
2 Check gas leakage on exhaust system.
NG Repair or replace exhaust gas leakage point.
OK
3 Check heated oxygen sensor (bank 1, 2 sensor 1) (See page SF-57).
HINT:
Refer to the hint following the end of this flowchart.
NG Replace heated oxygen sensor.
OK

DI-220
- DIAGNOSTICSENGINE
413 Author
: Date
:
4 Check heated oxygen sensor (bank 1, 2 sensor 2) (See page SF-57).
HINT:
Refer to the hint following the end of this flowchart.
NG Replace heated oxygen sensor.
OK
Replace the front and rear three-way catalyt-
ic converter in the bank a malfunction is de-
tected.
HINT:
Hand-held tester only:
The narrowing down the trouble area is possible by performing ACTIVE TEST of the following ºA/F CON-
TROLº (Heated oxygen sensor or another can be distinguished).
(a) Perform ACTIVE TEST by hand-held tester (A/F CONTROL).
HINT:
ºA/F CONTROLº is the ACTIVE TEST which changes the injection volume to -12.5 % or +25 %.
(1) Connect the hand-held tester to the DLC3 on the vehicle.
(2) Turn the ignition switch ON.
(3) Warm up the engine with the engine speed at 2,500 rpm for approximately 90 seconds.
(4) Select the item ºDIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / A/F CONTROLº.
(5) Perform ºA/F CONTROLº with the engine in an idle condition (press the right or left button).
RESULT:
Heated oxygen sensor reacts in accordance with increase and decrease of injection volume
+25 % " rich output: More than 0.5 V
-12.5 % " lean output: Less than 0.4 V

+25 %
-12.5 %
More than 0.5 V
Less than 0.4 V
Case 1
Case 2
Case 3
Case 4
Output voltage of heated oxygen
sensor (sensor 1: front sensor)
Injection volume
Output voltage
Output voltage of heated oxygen
sensor (sensor 2: rear sensor)Mainly suspect
trouble area
OK
+25 %
-12.5 %
More than 0.5 V
Less than 0.4 V
Injection volume
Output voltage
+25 %
-12.5 %
More than 0.5 V
Less than 0.4 V
Injection volume
Output voltage
Sensor 1: front sensor
(sensor 1, heater, sensor 1
circuit)
+25 %
-12.5 %
More than 0.5 V
Less than 0.4 V
Injection volume
Output voltage
+25 %
-12.5 %
Injection volume
Output voltage
NG
+25 %
-12.5 %
Injection volume
Output voltage
NG
+25 %
-12.5 %
Injection volume
Output voltage
NG
+25 %
-12.5 %
Injection volume
Output voltage
NGExtremely rich or lean of the
actual air-fuel ratio
(Injector, fuel pressure, gas
leakage in exhaust system,
etc.) OK
OK
OK
Almost no reaction
'
Sensor 2: rear sensor
(sensor 2, heater, sensor 2
circuit)
Almost no reactionAlmost no reaction
Almost no reaction
- DIAGNOSTICSENGINE
DI-221
414 Author
: Date
:
NOTICE:
However, there is a few second delay in the sensor 1 (front sensor) output. And there is about 20 se-
conds delay in the sensor 2 (rear sensor).
The following A/F CONTROL procedure enables the technician to check and graph the voltage output of
the heated oxygen sensors (sensor 1 and 2).
For displaying the graph indication, enter ºACTIVE TEST / A/F CONTROL / USER DATAº then select ºO2S
B1S1 and O2S B1S2º by pressing ºYESº button and push ºENTERº button before pressing ºF4º button.
NOTICE:
If the vehicle is short of fuel, the air-fuel ratio becomes LEAN and DTCs P0133 and/or P0153 will be
recorded, and the MIL then comes on.

If different DTCs related to different systems while terminal E2 as ground terminal are output simulta-
neously, terminal E2 may be open.

Read freeze frame data using the hand-held tester or the OBD II scan tool. Freeze frame data records
the engine conditions when a malfunction is detected. When troubleshooting, it is useful for determin-
ing whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio
was lean or rich, etc. at the time of the malfunction.

A high heated oxygen sensor (sensor 1) voltage (0.5 V or more) could be caused by a rich air fuel mix-
ture. Check for conditions that would cause the engine to run rich.

A low heated oxygen sensor (sensor 1) voltage (0.4 V or less) could be caused by a lean air fuel mix-
ture. Check for conditions that would cause the engine to run lean.