hood open LEXUS SC400 1991 Service Repair Manual

12. Observe the following precautions to avoid damage to theparts:
(a) Do not open the cover or case of the ECU unless
absolutely necessary (If the IC terminals are touched, the
IC may be destroyed by static electricity.).
(b) To pull apart electrical connectors, pull on the connectoritself, not the wires (See page BE±2).
(c) Be careful not to drop electrical components, such as sensors or relays. It they are dropped on a hard floor,
they should be replaced and not reused.
(d) When checking continuity at the wire connector, insert the tester probe carefully to prevent terminals from
bending.
(e) To disconnect vacuum hoses, pull on the end, not the middle of the hose.
(f) When steam cleaning an engine, protect the distributor,
coil and air filter from water.
(g) Ne ve r use an imp a ct wre n ch to re mo ve or in sta ll temperature switches or temperature sensors.
(h) When using a vacuum gauge, never force the hose onto
a connector that is too large. Use a step±down adapter
instead. Once the hose has been stretched, it may leak.
13. Tag hoses before disconnecting them: (a) When disconnecting vacuum hoses, use tags to identify
how they should be reconnected.
(b) After completing a job, double check that the vacuum hoses are properly connected. A label under the hood
shows the proper layout.
14. Installation of wheels The wheel assemblies are of the uni±directional type and
must be rotated only between the front and rear as illustrated.
Wheels are marked with turning direction indicators.
When installing the wheels, check the marks carefully and
install the wheel correctly.
15. Bleeding of traction control system When repairing the brake master cylinder or TRAC system,
bleed the air out of the TRAC system (See page BR±7).
CAUTION: Since the fluid is under high pressure, it could
spray out with great force, so be careful.
IN±6
±
INTRODUCTION General Repair Instructions
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REMOVAL OF HOOD LOCK CONTROL
(See page BO±24)
1. REMOVE FOLLOWING PARTS: (a) Front bumper
(b) LH front fender wheel opening moulding
(c) LH fender liner
(d) Fender splash shield
(e) Hood release lever
2. REMOVE HOOD LOCK (a) Remove two bolts, the nut and the hood lock.
(b) Disconnect the link from the lock.
3. REMOVE HOOD LOCK CONTROL CABLE (a) Disconnect the cable from clamps.
(b) Using the screwdriver, pry out the cable stopper fromgrommet.
HINT: Do not damage the grommet with the screwdriver.
±
BODY Hood (Hood Lock Control)BO±25
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(c) Pull the cable from front wheel housing to remove it.
INSTALLATION OF HOOD LOCK
CONTROL
(See page BO±24)
1. BEFORE INSTALLING PARTS, COAT LOCK WITH MP GREASE
Apply MP grease to the sliding surface of the lock.
2. INSTALL HOOD LOCK CONTROL CABLE (a) Push the rear side cable through the grommet.
(b) Using the screwdriver, push the cable stopper into thegrommet.
HINT: Do not damage the grommet with the screwdriver.
(c) Clamp the cable to the junction block.
(d) Pass the front side cable through the upper radiator
support.
3. INSTALL HOOD RELEASE LEVER
4. INSTALL HOOD LOCK TEMPORARILY
5. CHECK HOOD LOCK CONTROL FOR PROPER OPERATION
After checking for proper operation, tighten the nut and two
bolts to install the lock.
6. INSTALL FOLLOWING PARTS: (a) Hood release lever
(b) Fender splash shield
(c) LH fender liner
(d) LH front fender wheel opening moulding
(e) Front bumper
BO±26
±
BODY Hood (Hood Lock Control)
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GENERAL MAINTENANCE
MA00M±03
There are the maintenance and inspection
items which are considered to be the owner's
responsibility. They can be performed by the
owner or be can have them done at a service
shop. These items include those which should
be checked on a daily basis, those which, in
most cases, do not require (special) tools and
those which are considered to be reasonable
for the owner to perform. Items and procedures
for general maintanance are as follows:
MA00P±04
OUTSIDE VEHICLE
1. TIRES
(a) Check the pressure with a gauge. Adjust ifnecessary.
(b) Check for cuts, damage or excessive wear.
2. WHEEL NUTS Wheel checking the tires, check the nuts for
looseness or for missing nuts. If necessary,
tighten them.
3. TIRE ROTATION It is recommended that tires be rotated every
12,000 km (7,500 miles).
4. WINDSHIELD WIPER BLADES Check for wear or cracks whenever they do not
wipe clean. Replace if necessary.
5. FLUID LEAKS
(a) Check underneath for leaking fuel, oil, water or
other fluid.
(b) If you smell gasoline fumes or notice any leak, have the cause found and corrected.
6. DOORS AND ENGINE HOOD
(a) Check that all doors including the trunk lid operate smoothly, and that all latches lock
securely.
(b) Check that the engine hood secondary latch secures the hood from opening when the
primary latch is released.
MA00R±05
INSIDE VEHICLE
7. LIGHTS
(a) C h e c k t h a t t h e h eadlights, stop lights,
tail±lights, turn signal lights, and other lights
are all working. (b) Check the headlight aiming.
8. WARNING LIGHT AND BUZZERS
Check that all warning lights and buzzers func-
tion properly.
9. HORN Check that it is working.
10. WINDSHIELD GLASS
Check for scratches, pits or abrasions.
11. WINDSHIELD WIPER AND WASHER
(a) Check operation of the wipers and washer.
(b) Check that the wipers do not streak.
12. WINDSHIELD DEFROSTER Check that the air comes out from the defroster
outlet when operating the heater air condition-
er at defroster mode.
13. REAR VIEW MIRROR
Check that it is mounted securely.
14. SUN VISORS Check that they move freely and are mounted
securely.
15. STEERING WHEEL Check that it has the specified freeplay. Be
alert for changes in steering condition, such as
hard steering, excessive freeplay or strange
noise.
16. SEATS
(a) Check that all front seat controls such as seat adjusters, seatback recliner, etc. operate
smoothly.
(b) Check that all latches lock securely in any position.
(c) Check that the locks hold securely in any latched position.
(d) Check that the head restraints move up and
down smoothly and that the locks hold securely
in ay latches position.
(e) For folding±down rear seat backs, check that the latches lock securely.
17. SEAT BELTS
(a) Ch e ck th a t th e se a t be lt syste m su ch as buckles, retractors and anchors operate
properly and smoothly.
(b) Check that the belt webbing is not cut, frayed,
worn or damaged.
18. ACCELERATOR PEDAL Check the pedal for smooth operation and un-
even pedal effort or catching.
±
MAINTENANCE (1UZ ± FE)MA±19
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OVERALL ELECTRICAL WIRING DIAGRAM
1234
17 LEXUS SC300 (
Cont . ne xt pa ge )
4 ACC
IG1
ST1
AM1 3
2
1J
7 1B
21J 51J822
1B
51E 11
1E
51K 7 1K
13 1I 14 22
1H
10
1B
4
1
4 9IJ1 4IJ19IE1
8BY1 8 BT1 14 IE1 7 BT1 9 IP1 17 IG1 15 IF2 14 IF2 1 2
8A +B 2 2A
IG 7B
ACC 4B
SH 20 A
+B1 5B
HE AD 13 B
TAI L 1A
SRLY 11 B
HORN 8B
DS WP
10 B DS WL
12 B DSWH
1B LUG
5ATO
19 ATSW
6AKSW
14 AL1
10 AUL 3
3 1 2
1 1
2
2
1 1
BL BM EA IF 3F
7
3A
1
18
1E 10
1D
1
1J
16 A
E
15 AUL 1
18 A UL2
17 A LSWP
5IF2 4IF2 5IP1 14IP1 8IP1 19IP1 12 A
PCTY 7A
LSWP 4A
ACT+ 3A
ACT± 11 A
LSWD 13 A
DS WD
LOCK
UNLOCK
IJ
IF 20 IP12
31
1
3
2
LOCK
UNLOCK
1
2
8
LOCK
UNLOCK
1
3
2
LOCK
UNLOCK
G±W G± Y Y
R±B
W± L L±W L±R
P± B
R± W R
G±Y G±W
W±B
W±B
W± B
W± B
W± B G± Y
R± B G±L
W
R
R±Y
G±W L±O
G±R Y±R
R± W P± B
L±R
L±W
W± L R±B R
W
B±O
L±R
B±R
L±W L±W
W
W
W
R W
W± L
W
W± L
W± L
W
L±R
L±G
G±L
R±W
B
W±B
L
Y G±Y
G
R±B G±L
G±Y
G±W
G±W G± YG± L
R±B G± L
R±B G
G± Y
W±B
W± B W± B W± B
R
W±B
W±B
W± B
W± B W±B
R± L
B±Y
B±O
4 1
3 2
60A MAIN
100A AM1
120A ALT
40A
IGSW
F9
FUSE BL OCK I15
IGNITION SW
30A
DOOR
15A
ECU±
IG15A
CI G
25A
HAZ±HORN 10A
DOME
T1
THEFT DET ERRENT
HORN
THEFT DETERRENT AND DOOR LOCK ECU
F10
FUEL LID
OPENER SW
L±R
L±G
G± L
R± W
B
L
BATTERY
F14
FUEL LID OPENER
SOLENOID
L5
LUGGAGE COMPARTMENT
KEY UNLOCK SW E5
ENGI NE HOOD
COURTE SY SW
To Luggage Compartment
Light SW< 6±3> L4
LUGGAGE COMPARTMENT
DOOR OPENER MOT OR
L1
LUGGAGE COMPARTMENT
DOOR OPENER SW
To UNLOCK WARNING SW
<4±4><5±4>D7
DOORKEYLOCKAND
UNLOCK SW LH
P5
DOOR LOCK CONT ROL S W LH
[ POWER WI NDOW MASTER SW] Fr om Headlight Relay
<4±2><5±3>
From Taillight Relay
<4±3><5±3>
Fr om Sterter Relay
<1±3><2±2>
Fr om Hor n Rel ay
< 13±1>
To Power Main Relay
< 12±4>
D9
DOOR LOCK CONT RL
SW RH
D8
DOORKEYLOCKAND
UNLOCK SW RH
Power
Source Theft Deterrent and Door Lock Control
W± L
B±YR± L
6 2
7 T8 B , T9 A
Fr om Tilt and Power
Telesc opic ECU< 11±1>
Y
Under the center
pillar RH Ba ck
panel
centerFro nt si d e of
right fender
Lef t kic k panel
Left k ick panel Right k ick
panel
R± B
M6
5
5
6
2IG19A
To Trip SW and
Theft Deterr ent
I ndic ator Light
< 21±4>
G± B G± BIND
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11 3
M
64 5 31 2
1K
4
2
2
2 2
I11
B7 B7 I11
EB1
3 IE1
15
IP1
20
IP1
8IP1 19
IP 1
15 IP1 6IP1 18 IP1 5IP114 IE 1
14 BT1 9
IP1
7
A
15 UL1
A
12 DSWP
A
7 LSW P
A
3 ACT±
A
4 ACT+
B
12 DS WH
A
5 TOA
1
SRLY25 13
2
31
2
31
IJ EA
2 1
PRND 2 L
146578 9
GR
R±B
L
G±W G
W
A/T INDICATOR SW
[NEUTRAL START SW AND BACK±UP LIGHT SW]
N1
2
3
FROM POWER SOYURCE SYSTEM
(
SEE PAGE 56 )
7. 5A
ST
P
N STARTER
RE LA Y
THEFT DETERRENT AND DOOR LOCK ECU
LOCK
UNLOCK
LOCK
UNLOCK
DOOR KEY LOCK AND
UNLOCK SW RH
DOOR LOCK MOTOR,
DOOR UNLOCK DETE CTION AND
DOOR OPEN DETECTION SW RH DOOR LOCK
CONTROL SW RHENGINE HOOD
COURTESY SW
LUGGAGE COMPARTMENT
DOOR OPENER MOTOR
G± Y G±L
R±B
L±W
L±R W±B
L±R L±R B
Y
W
B
L±O B
B
L±O
B
G±L L±R
G±L B
W±B W±B
L±R
W±B W±B W±B
W±B W±B
L±R R±BG±L
L±W
P±B
R±W G±W
G±Y G±Y
G±W
R±W P±B
L±W
R±BG±L L±W
P±B
R±W
G±W
L4 E5
D9
D11 D8
T8
,T
9
B A
M
1
IJ1
6
B±W
( A/T )
IJ28
B±W B
( M/T )(
M/T)
B±W
( A/T )
B±W
( M/T )
CLUTCH STA RT
SW (
M/T )
C23
( A/T )
B3 3
W±BW±B
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11 6
THEFT DETERRENT AND DOOR LOCK CONTROL
D 7, D 8 DOOR KEY LOCK AND UNLOCK SW LH, RH
1±2 : CLOSED WITH DOOR LOCK CYLINDER UNLOCKED WITH KEY
3±2 : CLOSED WITH DOOR LOCK CYLINDER LOCKED WITH KEY
D10, D11 DOOR LOCK MOTOR, DOOR UNLOCK DETECTION SW AND DOOR OPEN DETECTION SW LH, RH
1±4: CLOSED WITH UNLOCK POSITION
E 5 ENGINE HOOD COURTESY SW
1±2: CLOSED WITH ENGINE HOOD OPEN
I15 UNLOCK WARNING SW [IGNITION SW]
9±10: CLOSED WITH IGNITION KEY IN CYLINDER
L 5 LUGGAGE COMPARTMENT KEY UNLOCK SW
1±3: CLOSED WITH DOOR LOCK CYLINDER UNLOCK WITH KEY
L 6 LUGGAGE COMPARTMENT LIGHT SW
1±GROUND: CLOSED WITH DOOR OPEN
T 8(B) THEFT DETERRENT AND DOOR LOCK ECU
1±GROUND: CONTINUITY WITH LUGGAGE COMPARTMENT DOOR TO UNLOCK POSITION
12±GROUND: CONTINUITY WITH ENGINE HOOD OPEN
10±GROUND: CONTINUITY WITH LUGGAGE COMPARTMENT DOOR OPEN
7±GROUND: APPROX. 12 VOLTS WITH IGNITION SW AT ACC OR ON POSITION
T 9(A) THEFT DETERRENT AND DOOR LOCK ECU
1±GROUND: APPROX. 12 VOLTS WITH SHIFT LEVER IN N OR P POSITION AND IGNITION SW AT ST POSITION
2±GROUND: APPROX. 12 VOLTS WITH IGNITION SW AT ON POSITION
6±GROUND: CONTINUITY WITH IGNITION KEY IN CYLINDER
7±GROUND: CONTINUITY WITH FRONT RH DOOR TO UNLOCK POSITION
8±GROUND: ALWAYS APPROX. 12 VOLTS
10±GROUND: CONTINUITY WITH DOOR LOCK KEY SW LH TO UNLOCK POSITION
11±GROUND: CONTINUITY WITH FRONT LH DOOR TO UNLOCK POSITION
12±GROUND: CONTINUITY WITH FRONT RH DOOR OPENED
13±GROUND: CONTINUITY WITH FRONT LH DOOR OPENED
14±GROUND: CONTINUITY WITH DOOR LOCK KEY SW RH TO LOCK POSITION
15±GROUND: CONTINUITY WITH DOOR LOCK KEY SW RH TO UNLOCK POSITION
20±GROUND: ALWAYS APPROX. 12 VOLTS
: PARTS LOCATION
CODESEE PAGECODESEE PAGECODESEE PAGE
C1428F 926N 127
C2328F1028P 531
D 730F1430T 127
D 830I1529T 8B29
D 930L 129T 9A29
D1030L 430T1529
D1130L 530
E 526L 630
: RELAY BLOCKS
CODESEE PAGERELAY BLOCKS (RELAY BLOCK LOCATION)
219ENGINE COMPARTMENT LEFT
422LEFT KICK PANEL (J/B NO.1 LEFT)
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CODESEE PAGEJUNCTION BLOCK AND WIRE HARNESS (CONNECTOR LOCATION)
1B20ENGINE ROOM MAIN WIRE
1D20FRONT DOOR LH WIRE
1E20INSTRUMENT PANEL WIRE
1H
1I20COWL WIRE1J20COWL WIRE
1K
3A22INSTRUMENT PANEL WIRE3F22INSTRUMENT PANEL WIRE
SERVICE HINTS
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