1996 TOYOTA LAND CRUISER INSTRUMENT PANEL

DI−80
−
DIAGNOSTICS ENGINE
1996 LAND CRUISER (RM451U)
DTC P0402 Exhaust Gas Recirculation Flow Excessive Detected
CIRCUIT DESCRIPTION
Refer to DTC P0401 (Exhaust Gas Recirculation Flow Insufficient Detected) on page DI−69.
DTC No.DTC Detecting ConditionTrouble Area
P0402
EGR gas temp. sensor value is high during EGR cut −off when
engine is cold (Race engine at about 4,000 rpm without load so
that vacuum is applied to port E)
(2 trip detection logic) EGR valve stuck open
 EGR VSV open malfunction
 Open in VSV circuit for EGR
 Short in EGR gas temp. sensor circuit
 ECM
EGR valve is always open (2 trip detection logic)
Refer to DTC P0401 (Exhaust Gas Recirculation Flow Insufficient Detected) for the System Check Driving
Pattern and Wiring Diagram.
INSPECTION PROCEDURE
TOYOTA hand −held tester
1 Connect the TOYOTA hand −held tester and read EGR gas temp. value.
PREPARATION:
(a) Remove the fuse cover on the instrument panel.
(b) Connect the TOYOTA hand−held tester to the DLC3.
(c) Turn ignition switch ON and push the TOYOTA hand −held tester main switch ON.
CHECK:
Read EGR gas temp. on the TOYOTA hand−held tester.
OK:
EGR gas temp.: 150° C (302°F) or less (Not immediately after driving)
HINT:
If there is a short circuit, the TOYOTA hand−held tester indicates Approx. 157.5°C (315.5°F).
OK Go to step 4.
NG
DI5PL−02
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A00174
ON
EGR Gas Temp.
Sensor 1
2 ECM
5V
E2
19
9
E4
E5 THG
BE6653
FI7054
A00175
ON
EGR Gas Temp.
Sensor ECM
5V
E2
E4 connector
THG
BE6653
FI7099
P22261
−
DIAGNOSTICS ENGINE
DI−81
1996 LAND CRUISER (RM451U)
2 Check for short in harness and ECM.
PREPARATION:
Disconnect the EGR gas temp. sensor connector.
CHECK:
Read EGR gas temp. on the TOYOTA hand−held tester.
OK:
EGR gas temp.: 3.1° C (37.6°F)
OK Replace EGR gas temp. sensor.
NG
3 Check for short in harness or ECM.
PREPARATION:
(a) Remove the instrument panel speaker No.1 panel. (See page SF−65 ).
(b) Disconnect the E4 connector of ECM.
HINT:
EGR gas temp. sensor is disconnected.
CHECK:
Read EGR gas temp. on the TOYOTA hand−held tester.
OK:
EGR gas temp.: 3.1° C (37.6°F)
OK Repair or replace harness or connector.
NG
Check and replace ECM (See page IN−28 ).
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A00176
ONSPD
(+)
(−)
BE6653
P24668
AT7809
9 − 14 V
0
Turn the wheel
DI−88
−
DIAGNOSTICS ENGINE
1996 LAND CRUISER (RM451U)
INSPECTION PROCEDURE
1 Check operation of speedometer.
CHECK:
Drive the vehicle and check if the operation of the speedmeter in the co\
mbination meter is normal.
HINT:
The vehicle speed sensor is operating normally if the speedometer displa\
y is normal.
NG Check speedometer circuit (See page BE−2 ).
OK
2 Check voltage between terminal SPD of ECM connector and body ground.
PREPARATION:
(a) Remove instrument panel speaker No.1 panel (See page SF−65 ).
(b) Disconnect cruise control ECU connector.
(c) Shift the shift lever to neutral.
(d) Jack up a rear wheels on one side.
(e) Turn ignition switch ON.
CHECK:
Measure voltage between terminal SPD of ECM connector and
body ground when the wheel is turned slowly.
OK:
Voltage is generated intermittently.
NG Check and repair harness and connector between combination meter and ECM.
OK
Check and replace ECM (See page IN−28 ).
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A00178
ONISC1 ISC3ISC2 ISC4
E4 connector
(−) (+)
BE6653
P24669
−
DIAGNOSTICS ENGINE
DI−91
1996 LAND CRUISER (RM451U)
INSPECTION PROCEDURE
1 Check air induction system (See page SF−1 ).
NG Repair or replace.
OK
2 Check voltage terminals ISC1, ISC2, ISC3, ISC4, of ECM connector and bod\
y ground.
PREPARATION:
(a) Remove instrument panel speaker No.1 panel (See page
SF−65 ).
(b) Disconnect the E4 connector of ECM.
(c) Turn ignition switch ON.
CHECK:
Measure voltage between terminals ISC1, ISC2, ISC3, ISC4 of
ECM connector and body ground.
OK:
Voltage: 9 − 14 V
OK Go to step 4.
NG
3 Check IAC valve (See page SF−49 ).
NG Replace IAC valve.
OK
Check for open and short in harness and co −nnector between EFI main relay (Marking:EFI) and
IAC valve and ECM (See page IN−28).
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−
DIAGNOSTICS ENGINE
DI−93
1996 LAND CRUISER (RM451U)
DTC P0510 Closed Throttle Position Switch Malfunction
CIRCUIT DESCRIPTION
Refer to DTC P0120 (Throttle/Pedal Position Sensor/Switch ”A” Circuit \
Malfunction) on page DI−35.
DTC No.DTC Detecting ConditionTrouble Area
P0510
The closed throttle position switch does not turn ON or OFF
even once when the vehicle is driven
(2 trip detection logic)Open or short in closed throttle position switch circuit
 Closed throttle position switch
 ECM
HINT:
After confirming DTC P0510 use the TOYOTA hand−held tester to confirm the closed throttle position switch
signal from ”CURRENT DATA”.
Throttle ValveClosed Throttle Position Switch SignalMalfunction
Fully closedOFFOpen circuit
Fully openONShort circuit
WIRING DIAGRAM
Refer to DTC P0120 (Throttle/Pedal Position Sensor/Switch ”A” Circuit Malfunction) on page DI−35 for WIR-
ING DIAGRAM.
INSPECTION PROCEDURE
HINT:
If DTCs P0110 (Intake Air Temp. Circuit Malfunction), P0115 (Engine Coolant Temp. Circuit Malfunction),
P0120 (Throttle/Pedal Position Sensor/Switch ”A” Circuit Malfunction)\
are output simultaneously, E2 (Sen-
sor Ground) may be open.
TOYOTA hand −held tester
1 Connect the TOYOTA hand −held tester and read CTP switch signal.
PREPARATION:
(a) Remove the fuse cover on the instrument panel.
(b) Connect OBD II scan tool or TOYOTA hand−held tester to the DLC3.
(c) Turn ignition switch ON and OBD II scan tool or TOYOTA hand−held tester main switch ON.
CHECK:
Read CTP switch signal on TOYOTA hand −held tester.
RESULT:
Throttle ValveClosed Throttle Position Switch SignalMalfunction
Fully closedOFFOpen circuit: Go to step 2
Fully openONShort circuit: Go to step 4
DI5PP−02
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BE6653
FI7058A00486
Throttle Position
SensorON
4
3
21
1
11
9
10
E5
E5
E5 E5
VTA
ECM
VCC
IDL
E2 E112V
5V
FI7064
A00487
Throttle Position Sensor
4
3
2
11
11
9
10
E5
E5
E5 E5
VTA
ECM
VCC
IDL
E2 E112V
5V
IDL E2
ON
DI−94
−
DIAGNOSTICS ENGINE
1996 LAND CRUISER (RM451U)
2 Check for open in harness or ECM.
PREPARATION:
(a) Disconnect throttle position sensor connector.
(b) Connect sensor wire harness terminals between terminals 1 and 2.
(c) Turn ignition switch ON.
CHECK:
Read CTP switch signal on TOYOTA hand −held tester.
OK:
CTP switch signal: ON
OK Confirm good connection at sensor. If OK, replace throttle position sensor.
NG
3 Check for open in harness or ECM.
PREPARATION:
(a) Remove instrument panel speaker No.1 panel (See page SF−65 ).
(b) Connect between terminals IDL and E2 of ECM.
HINT:
Throttle position sensor connector is disconnected.
Before checking, do a visual check and contact pressure check
for connector (See page IN−28).
(c) Turn ignition switch ON.
CHECK:
Read CTP switch signal on TOYOTA hand −held tester.
OK:
CTP switch signal: ON
OK Open in harness between ECM and throttle position sensor, repair or replace harness.
NG
Confirm connection at ECM.
If OK, replace ECM (See page IN−28).
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BE6653A00499A00488
Throttle Position Sensor
4
3
2
11
11
9
10
E5
E5
E5 E5
VTA
ECM
VCC IDL1
E2 E112V
5V
ON
BE6653
A00496 A00498
A00489
4
3
2
11
11
9
10
E5
E5
E5 E5
VTA1
ECM
VCC IDL1
E2 12V
5V
ON
Throttle Position
Sensor
E5 Connector
−
DIAGNOSTICS ENGINE
DI−95
1996 LAND CRUISER (RM451U)
4 Check for short in harness or ECM.
PREPARATION:
(a) Disconnect throttle position sensor connector.
(b) Turn ignition switch ON.
CHECK:
Read CTP switch signal on TOYOTA hand −held tester.
OK:
CTP switch signal: OFF
OK Confirm good connection at sensor. If OK, replace throttle position sensor.
NG
5 Check for short in harness or ECM.
PREPARATION:
(a) Remove instrument panel speaker No.1 panel (See page SF−65 ).
(b) Disconnect E5 connector of ECM.
HINT:
Throttle position sensor connector is disconnected.
(c) Turn ignition switch ON.
CHECK:
Read CTP switch signal on TOYOTA hand −held tester.
OK:
CTP switch signal: OFF
OK Short in harness between ECM and throttle position sensor, repair or replace harness.
NG
Confirm connection at ECM.
If OK, replace ECM (See page IN−28).
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A00183
ON(+)
(−)IGF
BE6653
P24673
DI−98
−
DIAGNOSTICS ENGINE
1996 LAND CRUISER (RM451U)
INSPECTION PROCEDURE
1 Check for spark (See page IG−1).
NG Go to step 4.
OK
2 Check for open and short in harness and connector in IGF signal circuit \
between ECM and igniter (See page IN−28).
NG Repair or replace harness or connector.
OK
3 Disconnect igniter connector and check voltage between terminal IGF of E\
CM connector and body ground.
PREPARATION:
(a) Disconnect igniter connector.
(b) Remove instrument panel speaker No.1 panel (See page
SF−65 ).
(c) Turn ignition switch ON.
CHECK:
Measure voltage between terminal IGF of ECM connector and
body ground.
OK:
Voltage: 4.5 − 5.5 V
OK Replace igniter.
NG
Check and replace ECM (See page IN−28 ).
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