TOYOTA LAND CRUISER 1998 Factory Repair Manual
Manufacturer: TOYOTA, Model Year: 1998, Model line: LAND CRUISER, Model: TOYOTA LAND CRUISER 1998Pages: 3115, PDF Size: 54.88 MB
Page 1111 of 3115
A21226
Wire Harness Side:
Mass Air Flow Meter Connector
M1
E2G VG
A21023
E5
ECM Connector E2G
VG
DI-62
- DIAGNOSTICSENGINE
255 Author: Date:
2004 LAND CRUISER (RM1071U)
4 Check for open and short in harness and connector between mass air flow meter
and ECM.
PREPARATION:
(a) Disconnect the M1 mass air flow meter connector.
(b) Disconnect the E5 ECM connector.
CHECK:
Check the resistance between the wire harness side connec-
tors.
OK:
Tester ConnectionSpecified Condition
VG (M1-5) - VG (E5-30)Below 1 W
E2G (M1-4) - E2G (E5-29)Below 1 W
VG (M1-5) or VG (E5-30) -
Body ground10 kW or higher
NG Repair or replace harness or connector.
OK
Replace mass air flow meter.
Page 1112 of 3115
A20872
Cowl Side J/B LH:
EFI or ECD
No. 2 Fuse
A21226
Wire Harness Side:
Mass Air Flow Meter Connector
M1
+B
A20871
Engine Room J/B:
EFI or ECD
Relay
- DIAGNOSTICSENGINE
DI-63
256 Author: Date:
2004 LAND CRUISER (RM1071U)
5 Check for open and short in harness and connector between mass air flow meter
and EFI or ECD relay.
Check EFI or ECD No. 2 fuse:
PREPARATION:
Remove the EFI or ECD No. 2 fuse from the cowl side J/B LH.
CHECK:
Check for continuity in the EFI or ECD No. 2 fuse.
OK:
Continuity
Check harness and connector:
PREPARATION:
(a) Install the EFI or ECD No. 2 fuse.
(b) Disconnect the M1 mass air flow meter connector.
(c) Remove the EFI or ECD relay from the engine room R/B.
CHECK:
Check the resistance between the wire harness side connec-
tors.
OK:
Tester ConnectionSpecified Condition
+B (M1-3) - Engine Room J/B (EFI or
ECD relay terminal 1)Below 1 W
+B (M1-3) or Engine room J/B (EFI or
ECD relay terminal 1) -
Body ground
10 kW or higher
NG Repair or replace harness or connector.
OK
Check ECM power source circuit
(See page DI-345).
Page 1113 of 3115
A21023
E2G E5
ECM Connector
A21226
Wire Harness Side:
Mass Air Flow Meter Connector
M1
VGE2G
A21023
E2G E5
ECM Connector VG
DI-64
- DIAGNOSTICSENGINE
257 Author: Date:
2004 LAND CRUISER (RM1071U)
6 Check continuity between terminal E2G of ECM connector and body ground.
CHECK:
Check the resistance between terminal of the E5 ECM connec-
tor and body ground.
OK:
Tester ConnectionSpecified Condition
E2G (E5-29) - Body groundBelow 1 W
NG Replace ECM (See page SF-60).
OK
7 Check for open in harness and connector between mass air flow meter and ECM.
PREPARATION:
(a) Disconnect the M1 mass air flow meter connector.
(b) Disconnect the E5 ECM connector.
CHECK:
Check the resistance between the wire harness side connec-
tors.
OK:
Tester ConnectionSpecified Condition
VG (M1-5) - VG (E5-30)Below 1 W
E2G (M1-4) - E2G (E5-29)Below 1 W
VG (M1-5) or VG (E5-30) -
Body ground10 kW or higher
E2G (M1-4) or E2G (E5-29) -
Body ground10 kW or higher
NG Repair or replace harness or connector.
OK
Replace mass air flow meter.
Page 1114 of 3115
- DIAGNOSTICSENGINE
DI-65
258 Author: Date:
2004 LAND CRUISER (RM1071U)
DTC P0101 Mass or Volume Air Flow Circuit Range/
Performance Problem
CIRCUIT DESCRIPTION
Refer to DTC P0100, P0102 and P0103 on page DI-57.
DTC No.DTC Detecting ConditionTrouble Area
P0101
After engine is warmed up, conditions (a), (b), (c) and (d) con-
tinue for more than 10 seconds:
(2 trip detection logic)
(a) Throttle valve fully closed
(b) Voltage output of the mass air flow meter is more than 2.2
V.
(c) Engine coolant temperature is more than 70 °C (158 °F).
(d) Engine speed is less than 900 rpm.
Mass air flow meter
Conditions (a), (b) and (c) continue for more than 6 seconds
with engine speed: (2 trip detection logic)
(a) Engine speed is more than 0 rpm.
(b) VTA is more than 0.1 V.
(c) Voltage output of the mass air flow meter is less than 0.25
V.
MONITOR DESCRIPTION
The MAF (Mass Air Flow) meter helps the ECM calculate the amount of air flowing through the throttle valve.
The ECM uses this information to determine the fuel injection time and provide a proper air fuel ratio. Inside
the MAF meter, there is a heated platinum wire exposed to the flow of intake air. By applying a specific current
to the wire, the ECM heats this wire to a given temperature. The flow of incoming air cools the wire and an
internal thermistor, affecting their resistance. To maintain a constant current value, the ECM varies the volt-
age applied to these components in the MAF meter. The voltage level is proportional to the air flow through
the MAF meter. The ECM interprets this voltage as the intake air amount. If there is a defect in the MAF meter
or an open or short circuit, the voltage level will deviate outside the normal operating range. The ECM inter-
prets this deviation as a defect in the MAF meter and sets a DTC.
Example:
If the voltage is more than 2.2 V at idle or less than 0.25 V at idle OFF, the ECM interprets this as a defect
in the MAF meter and sets a DTC.
MONITOR STRATEGY
Related DTCsP0101Mass air flow meter rationality
Main sensors/componentsMass air flow meter
Required sensors/componentsRelated sensors/componentsEngine speed sensor, Engine coolant tempera-
ture sensor, Throttle position sensor
Frequency of operationContinuous
Duration10 sec. (High voltage)
6 sec. (Low voltage)
MIL operation2 driving cycles
Sequence of operationNone
DI1LC-17
Page 1115 of 3115
DI-66
- DIAGNOSTICSENGINE
259 Author: Date:
2004 LAND CRUISER (RM1071U)
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)
High voltage:
Engine speed-900 rpm
IdleON
Engine coolant temperature70C (158F)-
Low voltage:
Engine speed0 rpm-
Throttle position0.1 V-
TYPICAL MALFUNCTION THRESHOLDS
Detection CriteriaThreshold
Mass air flow meter voltage (High voltage)More than 2.2 V
Mass air flow meter voltage (Low voltage)Less than 0.25 V
Page 1116 of 3115
- DIAGNOSTICSENGINE
DI-67
260 Author: Date:
2004 LAND CRUISER (RM1071U)
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, and other data from the time the malfunction occurred.
1 Are there any other codes (besides DTC P0101) being output?
PREPARATION:
(a) Connect the hand-held tester or the OBD II scan tool to 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 ll scan tool.
RESULT:
Display (DTC output)Proceed to
ºP0101º and other DTCsA
Only P0101B
HINT:
If any other codes besides P0101 are output, perform the troubleshooting for those codes first.
B Replace mass air flow meter.
A
Go to relevant DTC chart (See page DI-36).
Page 1117 of 3115
- 20 0 20 40 60 80 100
(- 4) 32 68 104 140 176 212 30
20
10
5
3
2
1
0.5
0.3
0.2
0.1
A21047
Acceptable (Fig.1)
Resistance KW
Temp. C (F)
DI-68
- DIAGNOSTICSENGINE
261 Author: Date:
2004 LAND CRUISER (RM1071U)
DTC P0110 Intake Air Temperature Circuit
DTC P0112 Intake Air Temperature Circuit Low Input
DTC P0113 Intake Air Temperature Circuit High Input
CIRCUIT DESCRIPTION
The intake air temperature (IAT) sensor, mounted on the mass
air flow (MAF) meter, monitors the intake air temperature. The
IAT sensor has a thermistor that varies its resistance depending
on the temperature of the intake air. When the air temperature
is low, the resistance in the thermistor increases. When the tem-
perature is high, the resistance drops. The variations in resis-
tance are reflected as voltage changes to the ECM terminal.
(See Fig. 1).
The intake air temperature sensor is connected to the ECM
(See below ). The 5 V power source voltage in the ECM is ap-
plied to the intake air temperature sensor from terminal THA
(THAR) via resistor R.
That is, the resistor R and the intake air temperature sensor are
connected in series. When the resistance value of the intake air
temperature sensor changes in accordance with changes in the
intake air temperature, the voltage at terminal THA (THAR) also
changes. Based on this signal, the ECM increases the fuel in-
jection volume to improve the driveability during cold engine op-
eration.
DTC No.Proceed toDTC Detection ConditionTrouble Area
P0110Step 1
Open or short in intake air
temperature sensor circuit for
0.5 sec.
Open or short in intake air temperature sensor circuit
P0112Step 4Short in intake air tempera-
ture sensor circuit for 0.5 sec.
Open or short in intake air temperature sensor circuit
Intake air temperature sensor (built in mass air flow meter)
ECM
P0113Step 2Open in intake air tempera-
ture sensor circuit for 0.5 sec.
ECM
HINT:
After confirming DTC ºP0110, P0112 or P0113º, use the hand-held tester or the OBD II scan tool to confirm
the intake air temperature in the ºDIAGNOSIS / ENHANCED OBD II / DATA LIST / ALLº.
Temperature DisplayedMalfunction
-40°C (-40°F)Open circuit
140°C (284°F) or moreShort circuit
DI1LE-13
Page 1118 of 3115
- DIAGNOSTICSENGINE
DI-69
262 Author: Date:
2004 LAND CRUISER (RM1071U)
MONITOR DESCRIPTION
The ECM monitors the sensor voltage and uses this value to calculate the intake air temperature. When the
sensor output voltage deviates from the normal operating range, the ECM interprets this as a fault in the IAT
(Intake Air Temperature) sensor and sets a DTC.
Example:
When the sensor voltage output equal to -40C (-40F), or more than 140C (284F).
MONITOR STRATEGY
P0110Intake air temperature sensor range check
(Fluttering)
Related DTCsP0112Intake air temperature sensor range check
(Low resistance)
P0113Intake air temperature sensor range check
(High resistance)
Required sensors/componentsIntake air temperature sensor
Frequency of operationContinuous
Duration0.5 sec.
MIL operationImmediate
Sequence of operationNone
TYPICAL ENABLING CONDITIONS
The monitor will run whenever the follow-
ing DTCs are not presentSee ºList of disable a monitorº (on page DI-3)
The typical enabling condition is not avail-
able-
TYPICAL MALFUNCTION THRESHOLDS
Detection CriteriaThreshold
P0110:
Intake air temperature sensor resistance
(Intake air temperature)Less than 98.5 W, or more than 156 kW
(More than 140C (284F), or less than -40C (-40F)
P0112:
Intake air temperature sensor resistance
(Intake air temperature)Less than 98.5 W
(More than 140C (284F))
P0113:
Intake air temperature sensor resistance
(Intake air temperature)More than 156 kW
(Less than -40C (-40F))
COMPONENT OPERATING RANGE
ParameterStandard Value
Intake air temperature sensor resistance98.5 W (140C (284F)) to 156 kW (-40C (-40F))
Page 1119 of 3115
A19962
8
1 M1
Mass Air Flow Meter
Y-B
E528 E5 20
THA
E2
E1 R5V ECM
3 10
7
BR-W THA
E2IN2
If1 IN2 IW3
7 2
BR-W BR BRY-B Y-B
IW3 DI-70
- DIAGNOSTICSENGINE
263 Author: Date:
2004 LAND CRUISER (RM1071U)
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
If DTCs related to different systems that have terminal E2 as the ground terminal are output simulta-
neously, terminal E2 may have an open circuit.
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 determine if the vehicle was running or stopped, if the engine was warmed up or not, if the air-fuel
ratio was lean or rich, and other data from the time the malfunction occurred.
Page 1120 of 3115
- DIAGNOSTICSENGINE
DI-71
264 Author: Date:
2004 LAND CRUISER (RM1071U)
1 Connect OBD II scan tool or hand-held tester, and read value of intake air tem-
perature.
PREPARATION:
(a) Connect the OBD II scan tool or the hand-held tester to the DLC3.
(b) Turn the ignition switch ON and push the OBD II scan tool or the hand-held tester main switch ON.
(c) When using hand-held tester, enter the following menus: DIAGNOSIS / ENHANCED OBD II / DATA
LIST / ALL / INTAKE AIR.
CHECK:
Read the temperature value on the OBD II scan tool or the hand-held tester.
OK:
Same as actual intake air temperature.
RESULT:
Temperature DisplayedProceed to
-40°C (-40°F)A
140°C (284°F) or moreB
OK (Same as present temperature)C
HINT:
If there is an open circuit, the OBD II scan tool or the hand-held tester indicates -40°C (-40°F).
If there is a short circuit, the OBD II scan tool or the hand-held tester indicates 140°C (284°F) or more.
B Go to step 4.
C Check for intermittent problems
(See page DI-3).
A