1996 TOYOTA LAND CRUISER Terminal

P22474
EBBR
22 22
1 3
4
2 2
2
R−Y R/B No.2
From BatteryR
Y−R
EA2
EB1
Y−RY −R
Y−R R
R−G
R−B
G−Y
Y−L
4
1
3 6
IAC Valve MRLY
E7
E4
E4
E4
E4 7 3
6
5
4
ISC1
ISC2
ISC3
ISC4 B+
E01
E01
E01
E01
EFI
2
5
EFI Main
Relay
7
1 ECM
A00202
ISC1
ISC2
ISC3
ISC4 A/C Switch OFF
→ ON
(IAC Valve Open)
20 V/Division
10 msec./Division
ISC1
ISC2
ISC3
ISC4 20 V/
Division
10 msec./Division
(IAC Valve Close)
A/C Switch ON →
OFF
FI6536
FI6537
DI−90
−
DIAGNOSTICS ENGINE
1996 LAND CRUISER (RM451U)
WIRING DIAGRAM
Reference: INSPECTION USING OSCILLOSCOPE
With the engine idling measure wavefoms between terminals
ISC1, ISC2, ISC3, ISC4 and E01 of ECM when A/C switch ON
or OFF.
HINT:
The correct waveforms are as shown.
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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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A00203
CloseOpen Battery
Battery
B1
S1
S2 B2S4
S3
B1
S1 S2 B2S4S3
P24670
P24671
DI−92
−
DIAGNOSTICS ENGINE
1996 LAND CRUISER (RM451U)
4 Check operation of the IAC valve .
PREPARATION:
Remove IAC valve (See page SF−51).
CHECK:
(a) Connect the positive (+) leak from the battery to terminals
5 (B1) and 2 (B2), and the negative ( −) lead to terminals
4 (S1), −1 (S2), −6 (S3), −3 (S4) in that order.
(b) Connect the positive (+) lead from the battery to terminals
5 (B1) and 2 (B2), and the negative ( −) lead to terminals
3 (S4), − 6 (S3), −1 (S2), − 4 (S1) in that order.
OK:
(1) The valve moves to close direction.
(2) The valve moves to open direction.
HINT:
The ACTIVE TEST mode of the T OYOTA hand−held tester can
be used to change the step of the IAC valve as desired.
NG Repair or replace IAC valve.
OK
Check and replace ECM (See page IN−28 ).
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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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A00492
43
2
11
11
9
10
E5
E5
E5 E5
VTA
ECM
VCC
IDL
E2E1 12V
5V
ON
Throttle Position Sensor
DI−96
−
DIAGNOSTICS ENGINE
1996 LAND CRUISER (RM451U)
OBD II scan tool (excluding TOYOTA hand −held tester)
1 Check for open and short in harness or ECM.
PREPARATION:
(a) Disconnect throttle position sensor connector.
(b) Turn ignition switch ON.
CHECK:
Measure voltage between terminals 1 and 2 of throttle position
sensor connector.
OK:
Voltage: 9 − 14 V
OK Confirm good connection at sensor. If OK, replace throttle position sensor.
NG
2 Check for open and short in harness and connector between throttle posit\
ion sensor and ECM (See page IN−28).
NG Open or short in harness between ECM and
throttle position sensor.
OK
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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A00184
STARTIGT
(+)(−)
BE6653
P24674
FI6605
IGT signal waveform
5 m sec/Division (Idling)
IGT
IGF
2 V/Div.
0V 0V
−
DIAGNOSTICS ENGINE
DI−99
1996 LAND CRUISER (RM451U)
4 Check for open and short in harness and connector in IGT signal circuit betwe\
en
ECM and igniter (See page IN−28).
NG Repair or replace harness or connector.
OK
5 Check voltage between terminals IGT of ECM connector and body ground.
PREPARATION:
Remove instrument panel speaker No.1 panel (See page
SF−65 ).
CHECK:
Measure voltage between terminal IGT of ECM connector and
body ground when engine is cranked.
OK:
Voltage: More than 0.1 V and less than 4.5 V
Reference: INSPECTION USING OSCILLOSCOPE
During cranking or idling, check waveforms between terminals
IGT and E1 of engine control module.
HINT:
The correct regulator waveforms are as shown.
NG Check and replace ECM (See page IN−28 ).
NG
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A00184
STARTIGT
(+)(−)
BE6653
P24674
A00186
ON and START
3
BE6653
P24675
DI−100
−
DIAGNOSTICS ENGINE
1996 LAND CRUISER (RM451U)
6 Disconnect igniter connector and check voltage between terminals IGT of ECM
connector and body ground.
PREPARATION:
(a) Disconnect igniter connector.
(b) Remove instrument panel speaker No.1 panel (See page
SF−65 ).
CHECK:
Measure voltage between terminal IGT of ECM connector and
body ground when engine is cranked.
OK:
Voltage: More than 0.1 V and less than 4.5 V
OK Check and replace ECM (See page IN−28 ).
NG
7 Check voltage between terminal 3 of igniter connector and body ground.
PREPARATION:
Disconnect igniter connector.
CHECK:
Measure voltage between terminal 3 of igniter connector and
body ground, when ignition switch is turned to ”ON” and
”START” position.
OK:
Voltage: 9 − 14 V
NG Check and repair igniter power source circuit.
OK
8 Check for open and short in harness and connector between ignition switc\
h and ignition coil, ignition coil and igniter (See page IN−28).
NG Repair or replace harness or connector.
OK
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