Page 759 of 1399
I00496
Cruise Control ECU
Fusible Link Fusible Link
Battery BR
BR
Instrument
Panel Fuse Block
ECU−IG
Ignition Switch BB
2
4 3
2
F6
1 JUNCTION
CONNECTOR J6
C17
C17B−W
I12
I12 4
2
2
2
2 B−W
F11
F11
B
B−Y
B
6EA2B
GND
13
14
AM1
FL AM1
1
ID
−
DIAGNOSTICS CRUISE CONTROL SYSTEM
DI−325
1996 LAND CRUISER (RM451U)
ECU Power Source Circuit
CIRCUIT DESCRIPTION
The ECU power source supplies power to the actuator and sensors, etc.. When\
terminal GND and the cruise
control ECU case are grounded.
WIRING DIAGRAM
DI5OM−02
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Page 761 of 1399
I00018
GND
−
DIAGNOSTICS CRUISE CONTROL SYSTEM
DI−327
1996 LAND CRUISER (RM451U)
3 Check resistance between terminal GND of cruise control ECU connector and
body ground (See page IN−28).
CHECK:
Measure resistance between terminal GND of ECU connector
and body ground.
OK:
Resistance: Below 1 Ω
NG Repair or replace harness or connector.
OK
Check and repair harness and connector be-
tween cruise control ECU and battery
(See page IN−28 ).
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Page 762 of 1399
I00497
Cruise Control ECU
B−R BATT
C17
W
W Instrument Panel Fuse Block
Fusible Link
F8 F11
F11
EA3
FL MAIN
Battery 3
ECU−B 15
2
1
N18670
Junction Block No.1
ECU−IG
Fuse
DI−328
−
DIAGNOSTICS CRUISE CONTROL SYSTEM
1996 LAND CRUISER (RM451U)
Back −up Power Source Circuit
CIRCUIT DESCRIPTION
The ECU back− up power source provides power even when the ignition is off and is used for DTC memory,
etc..
WIRING DIAGRAM
INSPECTION PROCEDURE
1 Check ECU −IG fuse.
PREPARATION:
Remove the ECU −IG fuse from relay block No.2.
CHECK:
Check continuity of ECU −IG fuse.
OK:
Continuity
NG Check for short in all the harness and compo- nents connected to the ECU −IG fuse.
OK
DI5ON−02
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I00016
BATT
(−)
(+)
−
DIAGNOSTICS CRUISE CONTROL SYSTEM
DI−329
1996 LAND CRUISER (RM451U)
2 Check voltage between terminal BATT of cruise control ECU connector and body
ground (See page IN−28).
PREPARATION:
Remove the ECU with connector still connected.
CHECK:
Measure voltage between terminal BATT of ECU connector
and body ground.
OK:
Voltage: 10 − 14 V
OK Proceed to next circuit inspection shown on problem symptoms table (See page DI−295 ).
NG
Check and repair harness and connector be-
tween battery and cruise control ECU
(See page IN−28 ).
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Page 766 of 1399
I00498
Cruise Control ECU
C17
Battery Fusible
Link
F6 B−L W
B
B G−Y
F11 F11
GAUGE
Y
2
Y9
CRUISE MAIN Indicator (Combination Meter)C10
C10
2 2 2
2
22
43
EA2
6
Ignition Switch
I12 I12
4
Instrument Panel Fuse Block
1
AM1
AM1 J1
JUNCTION
CONNECTOR
PI
7
DI−332
−
DIAGNOSTICS CRUISE CONTROL SYSTEM
1996 LAND CRUISER (RM451U)
CRUISE MAIN Indicator Light Circuit
CIRCUIT DESCRIPTION
When the cruise control main switch is turned ON, CRUISE MAIN indicator ligh\
t lights up.
WIRING DIAGRAM
DI5OP−02
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Page 783 of 1399

(a)
(b)
(c)
−
EMISSION CONTROL EXHAUST GAS RECIRCULATION (EGR) SYSTEM
EC−13
1996 LAND CRUISER (RM451U)
15. INSPECT VSV OPERATION
(a) Check that the air flows from pipe G to pipe E.
(b) Apply battery voltage across the terminals.
(c) Check that the air does not flows from pipe G to pipe E.
If operation is not as specified, replace the VSV.
16. RECONNECT VACUUM HOSES AND CONNECTOR
17. REINSTALL AIR INTAKE CHAMBER (See page
EM−54 )
18. DISCONNECT V ACUUM HOSES FROM EGR V ACUUM
MODULATOR
(a) Disconnect the vacuum hose from R port.
(b) Disconnect the vacuum hose from Q port.
(c) Disconnect the vacuum hose from P port.
19. INSPECT EGR VACUUM MODULATOR OPERATION
(a) Block ports P and R with your finger.
(b) Blow air into port Q, and check that the air passes through
to the air filter side freely.
(c) Start the engine, and maintain speed at 2,500 rpm.
(d) Repeat the above test. Check that there is a strong resis-
tance to air flow.
If operation is not as specified, replace the EGR vacuum modu-
lator.
20. RECONNECT VACUUM HOSES TO EGR VACUUM
MODULATOR
(a) Connect the vacuum hose to R port.
(b) Connect the vacuum hose to Q port.
(c) Connect the vacuum hose to P port.
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EM0KR−04
−
ENGINE MECHANICAL COMPRESSION
EM−3
506
Author: Date:
1996 LAND CRUISER (RM451U)
COMPRESSION
INSPECTION
HINT:
If there is lack of power, excessive oil consumption or poor fuel
economy, measure the compression pressure.
1. WARM UP AND STOP ENGINE
Allow the engine to warm up to normal operating temperature.
2. DISCONNECT DISTRIBUTOR CONNECTOR
3. REMOVE SPARK PLUGS (See page IG−1 )
4. CHECK CYLINDER COMPRESSION PRESSURE
(a) Insert a compression gauge into the spark plug hole.
(b) Fully open the throttle.
(c) While cranking the engine, measure the compression pressure.
HINT:
Always use a fully charged battery to obtain engine speed of
250 rpm or more.
(d) Repeat steps (a) through (c) for each cylinder.
NOTICE:
This measurement must be done in as short a time as pos-
sible. Compression pressure:
1,176 kPa (12.0 kgf/cm
2, 171 psi) or more
Minimum pressure: 883 kPa (9.0 kgf/cm
2, 128 psi)
Difference between each cylinder:
98 kPa (1.0 kgf/cm
2, 14 psi) or less
If the cylinder compression in one or more cylinders is low, pour
a small amount of engine oil into the cylinder through the spark
plug hole and repeat steps (a) through (c) for cylinders with low
compression.
If adding oil helps the compression, it is likely that
the piston rings and/or cylinder bore are worn or
damaged.
If pressure stays low, a valve may be sticking or
seating is improper, or there may be leakage past
the gasket.
5. REINSTALL SPARK PLUGS (See page IG−1 )
6. RECONNECT DISTRIBUTOR CONNECTOR
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EM1E3−01
EM−28
−
ENGINE MECHANICAL CYLINDER HEAD
1996 LAND CRUISER (RM451U)
REMOVAL
1. DRAIN ENGINE COOLANT
2. REMOVE BATTERY AND BATTERY TRAY
(a) Disconnect the battery cables.
(b) Remove the nuts, hold −down clamp and battery.
(c) Remove the bolt and disconnect the ground strap.
(d) Remove the 5 bolts and battery tray.
3. REMOVE AIR CLEANER HOSE AND CAP
4. DISCONNECT CRUISE CONTROL ACTUATOR CABLE FROM THROTTLE BODY
5. DISCONNECT ACCELERATOR CABLE FROM
THROTTLE BODY
6. DISCONNECT THROTTLE CABLE FROM THROTTLE BODY
7. DISCONNECT ENGINE GROUND STRAPS
(a) Disconnect the ground strap from the No. 1 engine hang-
er.
(b) Disconnect the ground strap from the air intake chamber.
8. DISCONNECT CONNECTOR ON INTAKE MANIFOLD FROM LH FENDER APRON
9. DISCONNECT BRAKE BOOSTER VACUUM HOSE
10. DISCONNECT EVAP HOSE
11. DISCONNECT FUEL RETURN HOSE
12. DISCONNECT HEATER HOSES
13. DISCONNECT ENGINE WIRE AND HEATER VALVE FROM COWL PANEL
(a) Remove the 2 bolts and disconnect the engine wire and
ground strap.
(b) Remove the 2 bolts and disconnect the heater valve.
14. REMOVE NO. 2 AND NO. 3 CYLINDER HEAD COVERS
Remove the 4 bolts and head covers.
15. REMOVE DISTRIBUTOR (See page IG−10 )
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