LEXUS SC400 1991 Service Repair Manual
Page 3021 of 4087
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POWER STEERING GEAR HOUSING
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Tie rod end X Steering knuckle 49 500 36
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Control valve shaft X Universal joint 35 360 26
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Pressure and return tube X Gear housing 49 500 36
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Gear housing installation bolt 76 770 56
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Pressure control valve X Control valve housing 18 185 13
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Rack housing X Control valve housing 18 185 13
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Control valve self±locking nut 39 400 29
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Rack housing cap 69 700 51
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Rack guide spring cap lock nut 56 570 41
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Rack X Rack end 92 940 68
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Tie rod end lock nut 56 570 41
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Turn pressure tube union nut 24 240 17
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Turn pressure tube union bolt 34 350 25
SR±172±
STEERING SERVICE SPECIFICATIONS
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Page 3022 of 4087
STEERING
SR±1
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Page 3023 of 4087
GENERAL DESCRIPTION
SR0E7±02
Care must be taken to replace parts properly because they could affect the p\
erformance of the steering
system and result in a driving hazard.
The steering wheel pad has an airbag built in, so take all due precautio\
ns when handling it. For more
details, see the RS section.
TROUBLESHOOTING
SR0E8±02
You will find the cause of trouble more easily by properly using the table \
shown below. In this table, the
numbers indicate the priority of the probable cause of trouble. Check each part in the order shown. If neces-
sary, repair or replace the part.
SA±3
SR±113SA±41
SR±167
SR±163
SA±16SA±3
SR±2±
STEERING GENERAL DESCRIPTION, TROUBLESHOOTING
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Page 3024 of 4087
GENERAL DESCRIPTION
SR0E7±02
Care must be taken to replace parts properly because they could affect the p\
erformance of the steering
system and result in a driving hazard.
The steering wheel pad has an airbag built in, so take all due precautio\
ns when handling it. For more
details, see the RS section.
TROUBLESHOOTING
SR0E8±02
You will find the cause of trouble more easily by properly using the table \
shown below. In this table, the
numbers indicate the priority of the probable cause of trouble. Check each part in the order shown. If neces-
sary, repair or replace the part.
SA±3
SR±113SA±41
SR±167
SR±163
SA±16SA±3
SR±2±
STEERING GENERAL DESCRIPTION, TROUBLESHOOTING
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Page 3025 of 4087
ON±VEHICLE INSPECTION
SR0E9±02
CHECK THAT STEERING WHEEL FREEPLAY IS COR-
RECT
With the vehicle stopped and tires pointed straight ahead,
rock the steering wheel gently back and forth with light finger
pressure.
Freeplay should not exceed the maximum.
Maximum freeplay:30 mm (1.18 in.)
If incorrect, repair.
±
STEERING ON±VEHICLE INSPECTIONSR±3
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Page 3026 of 4087
STEERING COLUMN
DESCRIPTION
SR0EA±02
There are two types of steering column, the manual tilt/manual telescopic one\
, and the power tilt/power
telescopic one.
SR0EB±02
OPERATION
POWER TILT OPERATIONThe power tilt mechanism consists of the control gear assembly, tilt motor, tilt position sensor, tilt and tele-
scopic switch, unlock warning switch and tilt and telescopic ECU.
The control gear assembly consists of the worm wheel, tilt gear, tilt worm and slider. Rotation of the tilt motor
moves the slider towards the tilt worm. The column upper tube is integrated w\
ith the slider and is rotated
up and down by movement of the slider.
SR±4
±
STEERING STEERING COLUMN
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Page 3027 of 4087
POWER TELESCOPIC OPERATION
SR0EC±02
The power telescopic mechanism is composed of the control gear assembly, telescopic motor, telescopic
position sensor, tilt and telescopic switch, unlock warning switch and tilt and telesco\
pic ECU.
The control gear assembly is composed of the worm wheel, telescopic scre\
w and slider. Rotation of the
telescopic motor moves the slider in the direction of the telescopic screw axis. The\
sliding tube is integrated
with the slider and is moved forward and backward by movement of the slider.
±
STEERING STEERING COLUMNSR±5
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Page 3028 of 4087
MANUAL TELESCOPIC OPERATION (SC300)
SR0ED±04
When the telescopic lever is pushed down, the lock bolt is rotated by the gear and the sliding tube is re-
leased by the lock wedges, allowing forward and backwards adjustment.
On the other hand, when the telescopic lever is pushed up, the lock wedges\
press the sliding tube against
the breakaway bracket to stop it from moving.
SR±6
±
STEERING STEERING COLUMN
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Page 3029 of 4087
PREPARATION
SST (SPECIAL SERVICE TOOLS)
SR0EE±04SR0EF±03
RECOMMENDED TOOLS
EQUIPMENT
SR0EG±02
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Torque wrench
±
STEERING STEERING COLUMNSR±7
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Page 3030 of 4087
ASSEMBLY REMOVAL AND
INSTALLATION
STEERING COLUMN ASSEMBLY
REMOVAL AND INSTALLATION
SR0NP±02
Remove and install the parts as shown.
SR±8
±
STEERING STEERING COLUMN
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