LEXUS SC400 1991 Service Repair Manual

mm (in.)
BO6852
BO6852
(Two-Dimensional Distance) (Three-Dimensional Distance)
SymbolName Hole dia.
Symbol Name Hole dia.
A, a Strut bar installation hole inner
14 (0.55)F, fLower arm installation hole front 26
y14
(1.02 y0.55)
B, b Differential carrier installation nut 12 (0.47) nut G, gRear suspension member standard
hole
20 (0.78)
C, c Rear suspension member standard
hole 20 (0.78)
H, hLower arm installation hole rear 26
y14
(1.02 y0.55)
D, d Lower arm installation hole front 26
yl4
1.02 y0.55 I, i
Upper arm installation hole rear 14 (0.55)
E, e Upper arm installation hole front 14 (0.55)
Suspension Crossmember (Cont'd)
BODY DIMENSIONSDI-12
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mm in.150
200
300 5.91
7.87
11.81
Replacement parts
QUARTER PANEL
HOW TO USE THIS MANUAL
Each repair method description provided in Section RE of this manual com\
prises two pages, divided into
2 blocks (REMOVAL AND INSTALLATION) and includes illustrations to facilitate body repair.
BODY PANEL REPLACEMENT-Rear Body Components
RE-40
QUARTER PANEL (CUT)REMOVAL Cut and Join Location
200 - 300 mm
150 - 200 mm
[Cut and Join Location]
Cut and Join Location
(Cut Location for Supply Parts)
1. Cut and join the parts at the location shown above.
HINT: Make incision and bend the roof drip channel at the upper part of the cur and join location.
REPLACEMENT PARTS AND METHOD
(CUT)
Replacement method(ASSY) Assembly replacement . . . . .
(CUT) Major cutting (less than 1/2 of parts used) . . . . . .
(CUT-H) Half cutting (about 1/2 of parts used) . . . .
(CUT-P) Partial cutting (most of parts used) . . . .
PARTS LOCATION
REMOVAL DIAGRAM
Describes in detail removal of the damaged parts involving repair by cut\
ting.
REMOVAL GUIDE
Provides additional information to more efficiently help you perform the removal.
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1. Before temporarily installing the new parts,apply body seater to the wheel arch.
HINT:
1) Apply body sealer about 5 mm (0.20 in.) from the flange, avoiding any oozing.
2) Apply sealer evenly, about 3 - 4 mm (0.12 - 0.16 in.) in diameter.
3) For other sealing points, refer to section AR.
RE 42 BODY PANEL REPLACEMENT-Rear Body Components
INSTALLATION
Butt Weld
Body Sealer
Butt Weld
Body Sealer
about 5 mm
2. Temporarily install the new parts and check thefit of the front door, luggage compartment door
and rear combination light.
3. Apply foamed material to the pillar section.
HINT: For the foamed material application areas, refer to page AP-00.
INSTALLATION DIAGRAM
Describes in detail installation of the new parts involving repair by we\
lding and/or cutting,
but excluding painting.
INSTALLATION GUIDE
Provides additional information to more efficiently help you perform the installation.
SYMBOLS
See page IN-4.
ILLUSTRATION OF WELD POINTS
Weld method and panel position symbols.
See page IN-5.
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SYMBOLSMEANING ILLUSTRATION
SAW CUT OR
ROUGH CUT
REMOVE BRAZE
(See page IN-5)
SPOT WELD OR
MIG PLUG WELD
WELD POINTS
BRAZE
CONTINUOUS MIG
WELD (BUTT WELD
OR TACK WELD)
BODY SEALER
SYMBOLS
The following symbols are used in the welding Diagrams in Section RE of \
this manual to indicate cutting
areas and the types of weld required.
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Remove weld point and panel positionWeld points
REMOVAL
Weld method and panel position
Weld points
INSTALLATION
SYMBOL MEANING ILLUSTRATION
SYMBOL
Spot WeldMEANING
ILLUSTRATION
Remove
Weld
Points
(Outside) Mig Plug
Weld
(Middle)
(Inside) Spot MIG
Weld
HINT: Panel position syrnbols are as seen from theworking posture.
Illustration of Weld Point Symbols
EXAMPLE:
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Steering Wheel Pad (Airbag and Inflator)
Junction Block No. 1 Center Airbag
Front Airbag Sensor
Front Airbag Sensor
Warning Light Spiral Cable (in Combination Switch)
HANDLING PRECAUTIONS ON RELATED COMPONENTS
1. SRS AIRBAG
Locations of Airbag Components
This vehicle has an SRS AIRBAG (referred to as the airbag in the remain\
der of this manual).
When handling airbag components (removal, installation or inspection, e\
tc.), always follow the directions
given in the repair manual for the relevant model year to prevent the oc\
currence of accidents and airbag
malfunction.
Also take the following precautions when repairing the body:

Work must be started after 20 seconds or longer from the time the ignitio\
n switch is set to the LOCK
position and the negative (-) terminal cable is disconnected from the \
battery.
(The airbag system is equipped with a back-up power source so that if w\
ork is started within 20 seconds
of disconnecting the negative (-) terminal cable of the battery, the airbag may be deployed.)
When the negative (-) terminal cable is disconnected from the battery, memory of the clock and audio
systems will be cancelled. So before starting work, make a record of the\
contents memorized by each
memory system. Then when work is finished, reset the clock and audio sys\
tems as before.
When the vehicle has tilt and telescopic steering, power seat, and outsi\
de rear view mirror, which are all
equipped with memory function, it is not possible to make a record of th\
e memory contents.
So when the operation is finished, it will be necessary to explain this \
fact to the customer, and request
the customer to adjust the features and reset the memory.
To avoid erasing the memory of each memory system, never use back-up powe\
r supply from outside
the vehicle.

When using electric welding, first disconnect the airbag connector (yel\
low color and 2 pins) under the
steering column near the combination switch connector before starting wo\
rk.
Sensor Assembly
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Front
Fender Area
Area from the Front Fender Apron
to the Cowl Side Member


Before repairing the body, remove the airbag sensors if, during repair, shocks are likely to, be applied
to the sensors due to vibrations of the body or direct tapping with tool\
s or other parts.

Do not expose the airbag sensors or the steering wheel pad directly to h\
ot air or flames.
NOTICE:
1) The maximum ambient temperature tolerance is 120
°C (248°F) for the front airbag sensor, 105°C
(221
°F) for the center airbag sensor assembly and 93°C (200°F) for the steering wheel pad. If it is
possible that the ambient temperature may reach or exceed the temperatur\
e limit, remove the sen- sors and the steering wheel pad from the vehicle or protect them with a \
hot insulation material be-fore starting work.
2) Prior to welding, remove adjacent airbag sensors or the steering wheel p\
ad from the vehicle or protect them with fire-proof covers.

If the front fender or periphery of the vehicle is damaged, visually ins\
pect for damage to the front air-
bag sensor using the inspection procedures described in section AB of th\
e repair manual for the rele-
vant model year.
Also check that the dimensions of the body where the front airbag sensor\
is installed match those in
the body dimension drawings.
(The airbag may malfunction; or may not work, if the mounting angle or \
dimensions of the sensor
mount are not correct.)

If the vehicle is damaged, visually inspect for damage to the steering w\
heel pad using the inspection
procedures described in section AB of the repair manual for the relevant\
model year.

When removing the steering wheel pad or handling a new steering wheel pa\
d, keep the pad upper
surface facing upward. Also, lock the lock lever of the twin lock type c\
onnector at the rear of the pad
and take care not to damage the connector.
(Storing the pad with its metallic surface up may lead to a serious acc\
ident if the airbag inflates for
some reason.)

Store the steering wheel pad where the ambient temperature remains below\
93 °C (200 °F), without
high humidity and away from electrical noise.

Be careful not to let painting materials contact the airbag sensors.

Information labels are attached to the periphery of the airbag component\
s. Follow the NOTICES.
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Shift Lock ECU
Tilt and Power
Telescopic ECU
Airbag ECU
Cruise Control ECU Engine ECUABS and Traction ECU
(w/ Traction System) or
ABS ECU
(w/o Traction System)
Theft Deterrent and
Door Lock ECU
(w/ Traction System)
Traction ECU
Remote Control Mirror ECU A/C Control Amplifier
PPS ECU
Engine Cooling Fan ECU
Component to be aligned
Section of repair manual
for relevant model year
Front Wheels Suspension and Axle (SA) section
Rear Wheels Suspension and Axle (SA) section
Propeller Shaft Propeller Shaft (PR) section
2. BRAKE SYSTEM
The brake system is one of the most important safety components. Always \
follow the directions and
notes given in section BR of the repair manual for the relevant model ye\
ar when handling brake sys-
tem parts.
NOTICE: When repairing the brake master cylinder or TRAC system, bleed t\
he air out of the TRAC
system.
3. DRIVE TRAIN AND CHASSIS
The drive train and chassis are components that can have great effects on the running performance
and vibration resistance of the vehicle. After installing components in \
the sections listed in the table
below, perform alignments to ensure correct mounting angles and dimensions. P\
articularly accurate
repair of the body must also be done to ensure correct alignment.
HINT: Correct procedures and special tools are required for alignment. Alway\
s follow the directionsgiven in the repair manual for the relevant model year during alignment \
and section DI of this manual.
4. ECU (ELECTRONIC CONTROL UNIT)
Locations of ECUs
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Fuel Pump ECUAuto Antenna Motor and Relay
Power Seat ECU
(For Passenger's Seat)
Power Seat ECU
(For Driver's Seat) CD Automatic Changer
Wireless Door Lock ECU
Moon Roof Control Relay
Locations of ECUs (Cont'd)
Many ECUs are mounted in this vehicle.
Take the following precautions during body repair to prevent damage to th\
e ECUs.


Before starting electric welding operations, disconnect the negative (-\
) terminal cable from the battery.
When the negative (-) terminal cable is disconnected from the battery, memory of the clock and audio
systems will be cancelled. So before starting work, make a record of the\
contents memorized by each
memory system. Then when work is finished, reset the clock and audio sys\
tems as before.
When the vehicle has tilt and telescopic steering, power seat and outsid\
e rear view mirror, which are all
equipped with memory function, it is not possible to make a record of th\
e memory contents.
So when the operation is finished, it will be necessary to explain this \
fact to the customer, and request
the customer to adjust the features and reset the memory.

Do not expose the ECUs to ambient temperatures above 80 °C (176 °F).
NOTICE: If it is possible the ambient temperature may reach 80°C (176°F) or, more, remove the ECUs
from the vehicle before starting work.

Be careful not to drop the ECUs and not to apply physical shocks to them\
.
5. COMPONENTS ADJACENT TO THE BODY PANELS
Various types of component parts are mounted directly on or adjacently to\
the body panels.
Strictly observe the following precautions to prevent damaging these com\
ponents and the body panels
during handling.

Before repairing the body panels, remove their adjacent components or ap\
ply protective covers over
the components.

Before prying components off using a screwdriver or a scraper, etc., attach protective tape to the tool
tip or blade to prevent damaging the components and the body paint.

Before removing components from the outer surface of the body, attach protective tape to the body to
ensure no damage to painted areas.
HINT: Apply touch-up paint to any damaged paint surfaces.

Before drilling or cutting sections, make sure that there are no wires, \
hoses, etc., on the reverse side.
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GENERAL REPAIR INSTRUCTIONS
Work Precautions
SAFETY
1. Before performing repair work, checkfor fuel leaks. If a leak is found, be sure
to close the opening totally.
2. If it is necessary to use a frame in the area of the fuel tank, first remove the
tank and plug the fuel line.
VEHICLE PROTECTION
When welding, protect the
painted surfaces, windows,
seats and carpet with heat
resistant, fire-proof covers.
SAFETY
Never stand in direct
line with the chain when
using a puller on the
body or frame, and be
sure to attach a safety
cable.
WRONG
Glass Cover
Safety Cable Seat Cover
WRONG
SAFETY WORK CLOTHES
HAND TOOLS
Keeping your hand tools in
neat order improve your
work efficiency.
In addition to the usual mechanic's wear, cap and safety shoes,
the appropriate gloves, head protector, glasses, ear plugs, face
protector, dust-prevention mask, etc. should be worn as, the
situation demands.
Dust-
Prevention
Mask Welder's
Glasses
Ear
Plugs Body
Mechanic
Stand
Face
Protector
Head
Protector
Eye
Protector
Welder's
Gloves
Safety
Shoes
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