engine LEXUS SC400 1991 Service Repair Manual

8. INSPECT CHARGING CIRCUIT WITH LOAD(a) With the engine running at 2,000 rpm, turn on the highbeam headlights and place the heater blower switch at
ºHIº.
(b) Check the reading on the ammeter.
Standard amperage: 30 A or more
If the ammeter reading is less than standard amperage, re-
pair the alternator. (See page CH±9)
HINT: With the battery fully charged, the indication will some-
times be less than standard amperage.
9. REINSTALL ENGINE UNDER COVER
CH±8
±
CHARGING SYSTEM On±Vehicle Inspection
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ALTERNATOR
COMPONENTS FOR REMOVAL AND
INSTALLATION
REMOVAL OF ALTERNATOR
1. DISCONNECT CABLE FROM NEGATIVE TERMINAL OFBATTERY
CAUTION: Work must be started after approx. 20 se-
conds or longer from the time the ignition switch is
turned to the ºLOCKº position and the negative (±) termi-
nal cable is disconnected from the battery.
2. REMOVE ENGINE UNDER COVER
3. REMOVE DRIVE BELT
Loosen the belt tension by turning the drive belt tensioner
counterclockwise, and remove the drive belt.
HINT: The pulley bolt for the belt tensioner has a left±hand
thread.
±
CHARGING SYSTEM AlternatorCH±9
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INSTALLATION OF ALTERNATOR
(See Components on page CH±9)
1. INSTALL ALTERNATOR (a) Install the alternator and A/T oil cooler bracket with the
bolt and nut.
Torque: 37 N Vm (380 kgf Vcm, 27 ft Vlbf)
(b) Connect the alternator connector.
(c) Connect the alternator wire with the nut and cap.
2. INSTALL DRIVE BELT Install the drive belt by turning the drive belt tensioner coun-
terclockwise.
HINT: The pulley bolt for the belt tensioner has a left±hand
thread.
3. CONNECT CABLE TO NEGATIVE TERMINAL OF BATTERY
4. PERFORM ON±VEHICLE INSPECTION (See steps 6 to 8 on pages CH±6 to 8)
5. INSTALL ENGINE UNDER COVER
CH±20
±
CHARGING SYSTEM Alternator
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Front Door Trim Upper Panel (ABS/PVC)
Battery Insulator (PE) Roof Side Inner Garnish (ABS/PVC)
Front Pillar Garnish (ABS/PVC)
Speed Control Actuator Cover (PP)
Radiator Reserver Tank (PP)
Radiator Cover Plate (PP) Cool Air Intake
Duct (PP)
Spare Wheel Cover (PP)
Washer Jar (PP)
Junction Block Cover (PP)
Front Fender Liner (PE)
Front Fender Splash Shield (PE)
Engine Under Cover (PE) Engine Under Cover (PE)
Engine Under Cover (PP/PE)
HINT:
wResin material differs with model.
/ Made up of 2 or more kinds of materials.
PLASTIC BODY PARTSPP-5
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mm in.1
1.5
3.5
4
4.8
5
5.5
6 0.04
0.06
0.14
0.16
0.19
0.20
0.22
0.24
FIT STANDARDS
After doors and the engine hood are installed, be sure to perform flit a\
djustment to prevent abnormal wind
noise and ensure a good appearance.
APPENDIXAP-2
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mm (in.)
BO6846
BO6860
1,218
(47.95)392
(15.43)
H-U
h-u
K-o
k-O 1,186
(46.69)
H-T
h-t
393
(15.47)
D-U
D-u 379
(14.92)
G-U
g-u
1,158
(45.59)
D-T
D-t G-T
g-t
366
(14.41)
1,299
(51.14)
D-S
D-s 151
(5.94)
1,260
(49.61)
D-R
D-r
J-S
j-s187
(7.36)
1,215
(47.83)
D-Q
D-q
J-R
j-r1,192
(45.92)
1,201
(47.28)
K-q
k-Q
D-P
D-p 1,033
(40.67)
1,143
(45.0)
K-p
k-P
D-O
D-o
Vehicle Dimensions
1,689
(66.50)
847
(33.35)
205
(8.19)
1,460
(57.48) C-K, c-k
C-K, c-k
A-K, a-k
A-a
Vehicle Dimensions
*1 851 (33.50)
(Three-Dimensional Distance)
Symbol Name Hole dia. Symbol Name Hole dia.
A, a Front fender apron standard hole 10 (0.39)
L, l Front fender installation nut
6 (0.24) nut
B, b Front spring support hole-front
11 (0.43)M, m Hood hinge installation nut-rear
8 (0.31) nut
C, c Cowl side panel standard hole
10 (0.39)N, n Front fender installation nut-rear
6 (0.24) nut
D Cowl top panel center mark
O, oHead light installation nut
6 (0.24) nut
E, e Front side member working hole
18 (0.71)P, pHead light installation nut
6 (0.24) nut
F, f Front side member working hole
18 (0.71)Q, qHead light installation nut
6 (0.24) nut
G, g Radiator support standard hole
10 (0.39)R, rHead light installation nut
6 (0.24) nut
H, h Radiator support standard hole
10 (0.39)S, sHead light installation hole
11 (0.43)
I, i Front fender apron standard hole 10 (0.39)T, t Head light installation hole 10 (0.39)
J, j Front side member standard hole
8 (0.31)U, u Head light installation hole 10 (0.39)
K, k Front fender installation nut-front
6 (0.24) screw
BODY DIMENSION DRAWINGS
ENGINE COMPARTMENT
BODY DIMENSIONSDI-3
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BO6847
mm (in.)
(Three-Dimensional Distance)
Hole dia.
10 (0.39) screw
14 (0.55) screw
10 (0.39) screw
Name
Propeller shaft center support bearing installation nut
Rear suspension member installation nut
Suspension member bracket installation nut rear = outer
Symbol
K, k
N, n
P, p
Hole dia.
9 (0.35)
18 (0.71)
10 (0.39) screw
Name
Front crossmember working hole
Front suspension crossmember installation nut
Engine rear mounting member installation hole
Symbol
B, bH, h J, j
UNDER BODY (Cont'd)
BODY DIMENSIONSDI-5
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BO6847
NOTICE: True up the mounting section ofthe front airbag sensor very carefully and
accurately so that the sensor can bemounted at the correct angle.
Imaginary
Standard
Line
mm (in.)
(Two-Dimensional Distance)
Hote dia.
10 (0.39) nut
10 (0.33) nut
18 (0.71)
14 (0.55) nut 9 (0.35)
Name
Engine rear mounting member installation nut-front Propeller shaft center support bearing installation nut
Front floor reinforcement standard hole
Rear suspension member installation nut Rear spring support hole-front
Symbol
J, j
K, k
L, l
N, n
O, o
Hole dia.
9 (0.35)
9 (0.35)
8 (0.31) nut
13 y11 (0.51 y0.43)14 (0.55) nut
Name
Front crossmember working hole
Airbag front sensor installation hole
Airbag front sensor installation nut Front spring support hole = outer
Front suspension crossmember installation nut
Symbol
B, b
C, c
E, e
G, g H, h
UNDER BODY (Cont'd)
BODY DIMENSIONSDI-7
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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
INTRODUCTIONIN-8
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INSTALLATION
PRE-WELDING MEASUREMENTS
Always take measurements
before installing underbody
or engine components
to insure correct assembly.
After installation, confirm
proper fit.POST-WELDING REFINISH-
ING
1. Always check the welded
spots to insure they are
secure.
2. When smoothing out the weld spots with a disc
grinder, be careful not to
grind off too much as this
would weaken the weld.
WELDING PRECAUTIONS
1. The number of welding spots
should be as follows.
Spot weld: 1.3 x No. of
manufacturer's spots.
Plug weld: More than No. of
manufacturer's plugs.
WRONG
OKAYWRONG
2. Plug welding should be done
with a MIG (Metal Inert Gas)
welder. Do not gas weld or
braze panels at areas other
than specified.
Safety Glass
Body
Measurement
Diagrams
SPOT WELDING PRECAUTIONS
SPOT WELD LOCATIONS
Try to avoid welding over
previous spots. 1. The shape of the welding
tip point has an effect on
the strength of the weld.
2. Always insure that the seams and welding tip are
free of paint.
Old
Spot
Locations New Spot
Locations
Tip Cutter
INTRODUCTIONIN-13
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