1991 LEXUS SC300 brake light

REAR DRIVE SHAFT REMOVAL
SA0S3±03
1. JACK UP VEHICLE AND REMOVE REAR WHEEL
2. REMOVE EXHAUST PIPE
3. REMOVE COTTER PIN, LOCK NUT CAP AND LOCK NUT
4. REMOVE REAR DRIVE SHAFT
(a) Place matchmarks on the drive shaft and side gear shaft.
NOTICE: Do not use a punch to mark the matchmarks. Use
paint, etc.
(b) Using a 10 mm hexagon wrench, remove the 6 hexagon bolts
and 2 washers while depressing the brake pedal.
(c) Hold the inboard joint side of the drive shaft so that the
outboard joint side does not bend too much.
(d) Using a plastic±faced hammer, lightly tap the end of the drive
shaft, disengage the axle hub and remove the drive shaft.
NOTICE:
w Be careful not to damage the boots, end cover and speed
sensor rotor of the drive shaft, and oil seal of the axle hub.
w Make sure the outboard joint side of the drive shaft does
not bend too much.
SA±66±
SUSPENSION AND AXLE REAR DRIVE SHAFT
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146
ABS (ANTI±LOCK BRAKE SYSTEM)
THIS SYSTEM CONTROLS THE RESPECTIVE BRAKE FLUID PRESSURES ACTING ON THE DISC\
BRAKE CYLINDERS OF THE RIGHT
FRONT WHEEL, LEFT FRONT WHEEL AND REAR WHEELS WHEN THE BRAKES ARE APPLIED IN \
A PANIC STOP SO THAT THE
WHEELS DO NOT LOCK. THIS RESULTS IN IMPROVED DIRECTIONAL STABILITY AND STEERABILITY DURING PANIC BRAKING.
1. INPUT SIGNALS
(1) SPEED SENSOR SIGNALTHE SPEED OF THE WHEELS IS DETECTED AND INPUT TO TERMINALS FL+, FR+, RL+ AND RR+ OF THE ABS ECU.
(2) STOP LIGHT SW SIGNAL A SIGNAL IS INPUT TO TERMINAL STP OF THE ABS ECU WHEN THE BRAKE PEDAL IS OPERATED.
(3) PARKING BRAKE SW SIGNAL A SIGNAL IS INPUT TO TERMINAL PKB OF THE ABS ECU WHEN THE PARKING BRAKE IS OPERATED.
2. SYSTEM OPERATION
DURING SUDDEN BRAKING, THE ABS ECU WHICH HAS SIGNALS INPUT FROM EACH SENSOR CONTROLS THE CURRENT FLOWING
TO THE SOLENOID INSIDE THE ACTUATOR AND LETS THE HYDRAULIC PRESSURE ACTING ON EACH WHEEL CYLINDER ESCAPE \
TO
THE RESERVOIR.
THE PUMP INSIDE THE ACTUATOR IS ALSO OPERATING AT THIS TIME AND IT RETURNS THE BRAKE FLUID FROM THE RESERVOIR
TO THE MASTER CYLINDER, THUS PREVENTING LOCKING OF THE VEHICLE WHEELS.
IF THE ECU JUDGES THAT THE HYDRAULIC PRESSURE ACTING ON THE WHEEL CYLINDER IS INSUFFICIENT, THE CURRENT
ACTING ON SOLENOID IS CONTROLLED AND THE HYDRAULIC PRESSURE IS INCREASED.
HOLDING OF THE HYDRAULIC PRESSURE IS ALSO CONTROLLED BY THE COMPUTER, BY THE SAME METHOD AS ABOVE. BY
REPEATED PRESSURE REDUCTION, HOLDING AND INCREASE ARE REPEATED TO MAINTAIN VEHICLE STABILITY AND TO IMPROVE
STEERABILITY DURING SUDDEN BRAKING.
A 4(B), A 33(A) ABS ACTUATOR
(A) 3, (A) 4±GROUND : ALWAYS APPROX. 12 VOLTS
(A) 1±GROUND : ALWAYS CONTINUITY
(B) 4, (B) 5, (B) 6±GROUND : APPROX. 1.15
(IGNITION SW OFF)
(B) 2±GROUND :APPROX. 5
(IGNITION SW OFF)
A 7, A 8, A30, A31 ABS SPEED SENSOR FRONT LH, RH, REAR LH, RH
1±2 : APPROX. 1.0KW (20 °C, 68°F)
A22(A), A23(B) ABS ECU
(B) 11±GROUND : APPROX. 12 VOLTS WITH IGNITION SW ON
(B) 2, (B) 13±GROUND : ALWAYS CONTINUITY
(B) 22±GROUND : ALWAYS APPROX. 12 VOLTS
(B) 1, (A) 6, (A) 12±GROUND : APPROX. 12 VOLTS WITH IGNITION SW ON
(B) 16±GROUND : CONTINUITY WITH PARKING BRAKE LEVER PULLED UP
(B) 7±GROUND : APPROX. 12 VOLTS WITH STOP LIGHT SW ON
P 3 PARKING BRAKE SW
1±GROUND : CLOSED WITH PARKING BRAKE LEVER PULLED UP
S12 STOP LIGHT SW
1±2 : CLOSED WITH BRAKE PEDAL DEPRESSED
SYSTEM OUTLINE
SERVICE HINTS
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136
ABS AND TRACTION CONTROL
I16E9
I14
I25 I25
I4
E13 I7
1E
12 1I 10 2 1I 8
14 8 17 4
IO1
8
IK2
9 3E
3
A1
B
15 B 5B1
B
22 GND1
B
2 GND2
B
13 GND3
B
6 LBL
B
17 PKB C
7 ABSO
C
12 BRP
C
8 BRC
C
7 THFA
C
11 BRFA
C
15 FRO
C
6 FL O
C
10 P
C
5 N
B
20
D/G B
10
STP B
21
BATT A
24
IG
3A
4
3D13
IK25 IO1
1IE2 7
1 2
I7 1H1
1E20
FROM POWER SOURCE SYSTEM
(
SEE PAGE 56 )
2 1 2 1
2 1 1
EA
IJ IG1
19 IG1 20IK2
18
IE2
12 IE1
1 IO1
9
P±B
Y
W
G±W
G±W
R
B±R
B±R R
G±W
Y
LG±R W
L V±W
L±Y W
G±W B±R
R±B
R±B
L
GR LG
LG±B P±L
P±G
V±R
B±Y
W±B
W±B
W±B
R±W
R±W
R±W
R±W
B
R±W
R±W
R±WR±B
B
W±B W±B W±B
V±W
L±Y
L
P±B
R±W R±W
B WW
R±W
10A
GAUGE
15A
STOP10A
DOME15A
ECU±IG
WTRC
ABS TC
G±W
COMBINATION METER STOP LIGHT
SW
TDCL
ABS AND TRACTION ECU
B
B
PARKING
BRAKE SW
BRAKE FLUID
LEVEL SW
DIODE
(FOR BRAKE FLUID LEVEL )
DIODE
( FOR P ARK I NG
BRAKE ) (
CANADA )
(
USA )
A24
,A2 5
,A26
C13
,
C14
T6 S12
P3
B1 D1
D2
B
A
B B±R
R
G± W
LG±R W
L±Y
B±Y
V±R
P±G P±L
LG±B LG
GR L
R±B
R±W
IK 1
10
3H
12
P±B
TRAC OFF TRAC ANTI
LOCK
A
B 2
1
P±B
P±B
P±B
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139
(FOR ABS)
THIS SYSTEM CONTROLS THE RESPECTIVE BRAKE FLUID PRESSURES ACTING ON THE DISC\
BRAKE CYLINDERS OF THE RIGHT
FRONT WHEEL, LEFT FRONT WHEEL AND REAR WHEELS WHEN THE BRAKES ARE APPLIED IN \
A PANIC STOP SO THAT THE
WHEELS DO NOT LOCK. THIS RESULTS IN IMPROVED DIRECTIONALLY STABILITY AND STEERABILITY DURING PANIC BRAKING.
1. INPUT SIGNALS
(1) SPEED SENSOR SIGNALTHE SPEED OF THE WHEELS IS DETECTED AND INPUT TO TERMINALS FL+, FR+, RL+ AND RR+ OF THE ABS AND TRACTION
ECU.
(2) STOP LIGHT SW SIGNAL A SIGNAL IS INPUT TO TERMINAL STP OF THE ABS AND TRACTION ECU WHEN THE BRAKE PEDAL IS OPERATED.
(3) PARKING BRAKE SW SIGNAL A SIGNAL IS INPUT TO TERMINAL PKB OF THE ABS AND TRACTION ECU WHEN THE PARKING BRAKE IS OPERATED.
2. SYSTEM OPERATION
DURING SUDDEN BRAKING, THE ABS AND TRACTION ECU WHICH HAS SIGNALS INPUT FROM E\
ACH SENSOR CONTROLS THE
CURRENT FLOWING TO THE SOLENOID INSIDE THE ACTUATOR AND LETS THE HYDRAULIC PRESSURE ACTING ON EACH WHEEL
CYLINDER ESCAPE TO THE RESERVOIR. THE PUMP INSIDE THE ACTUATOR IS ALSO OPERATING AT THIS TIME AND IT RETURNS
THE BRAKE FLUID FROM THE RESERVOIR TO THE MASTER CYLINDER, THUS PREVENTING LOCKING OF THE VEHICLE WHEELS.
IF THE ECU JUDGES THAT THE HYDRAULIC PRESSURE ACTING ON THE WHEEL CYLINDER IS INSUFFICIENT, THE CURRENT
ACTING ON SOLENOID IS CONTROLLED AND THE HYDRAULIC PRESSURE IS INCREASED, HOLD\
ING OF THE HYDRAULIC
PRESSURE IS ALSO CONTROLLED BY THE COMPUTER, BY THE SAME METHOD AS ABOVE. BY REP\
EATED PRESSURE REDUCTION,
HOLDING AND INCREASE ARE REPEATED TO MAINTAIN VEHICLE STABILITY AND TO IMPROVE STEERABILITY DURING SUDDEN
BRAKING.
(FOR TRACTION CONTROL)
THE TRACTION CONTROL SYSTEM IS A SYSTEM WHEREBY THE ªABS AND TRACTION ECUº AND ªTRACTION ECUº\
CONTROLS THE
ENGINE TORQUE AND THE HYDRAULIC PRESSURE OF THE WHEEL CYLINDER OF THE DRIVING WHEELS IN ORDER TO CONTROL
SPINNING OF THE DRIVING WHEELS WHEN STARTING OFF AND ACCELERATING, AND PROVIDE THE MOST APPROPRIATE DRIVING
FORCE IN RESPONSE TO THE ROAD CONDITIONS FOR VEHICLE STABILITY.
TRACTION CONTROL OPERATION
VEHICLE SPEED SIGNALS FROM THE SPEED SENSOR INSTALLED ON EACH WHEEL ARE INPUT TO THE ABS AND TRACTION ECU.
WHEN THE ACCELERATOR PEDAL IS DEPRESSED WHILE DRIVING ON A SLIPPERY ROAD AND THE DRIVING WHEEL (REAR WHEEL)
SLIPS, IF THE ROTATION OF THE REAR WHEEL EXCEEDS THE ROTATION OF THE FRONT WHEELS FOR A SPECIFIED PERIOD, THE
ECU JUDGES THAT THE REAR WHEEL IS SLIPPING.
WHEN THIS OCCURS, CURRENT FLOWS FROM TRACTION ECU TO SUB THROTTLE ACTUATOR TO CLOSE THE SUB THROTTLE
VALVE. THE THROTTLE VALVE OPENING ANGLE SIGNAL IS OUTPUT FROM TERMINAL VTA OF SUB THROTTLE POSITION SENSOR
TO TERMINAL VTA2 OF ENGINE AND ECT ECU TO KEEP THE ENGINE RPM AT THE MOST SUITABLE LEVEL FOR THE DRIVING
CONDITIONS AND REDUCE SLIP OF THE DRIVING WHEEL. AT THE SAME TIME, OPERATION OF THE ABS AND TRACTION ECU
CAUSE THE TRACTION BRAKE ACTUATORS (ACC CUT, M/C CUT, RESERVOIR CUT SOLENOID) TO TURN ON TO SWITCH THE
HYDRAULIC CIRCUIT TO ªTRACTIONº MODE.
IN THIS CASE, SIGNALS ARE INPUT FROM TERMINAL SRR OF ABS AND TRACTION ECU TO TERMINAL (B)6 OF ABS ACTUATOR, AND
FROM TERMINAL SRL OF ABS AND TRACTION ECU TO TERMINAL (B)1 OF ABS ACTUATOR, CONTROLLING THE REAR WHEEL
SOLENOID IN THE ABS ACTUATOR AND INCREASING THE HYDRAULIC PRESSURE OF THE WHEEL CYLINDER IN ORDER \
TO
PREVENT SLIP.
TO MAINTAIN THE HYDRAULIC PRESSURE OF THE REAR WHEELS, THE REAR WHEEL SOLENOID I\
NSIDE THE ABS ACTUATOR IS
PUT IN ªHOLDº MODE AND KEEPS THE HYDRAULIC PRESSURE TO THE BRAKE CYLINDER CONSTANT.
WHEN THE BRAKE CYLINDER HYDRAULIC PRESSURE IS REDUCED, THE PRESSURE REDU\
CTION MODE REDUCES AND CONTROLS
THE HYDRAULIC PRESSURE.
SYSTEM OUTLINE
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140
ABS AND TRACTION CONTROL
A24(A), A25(B), A26(C) ABS AND TRACTION ECU
(B) 21±GROUND : ALWAYS APPROX. 12 VOLTS
(B) 11±GROUND : APPROX. 12 VOLTS WITH IGNITION SW AT ON POSITION
(B) 10±GROUND : CONTINUITY WITH STOP LIGHT SW ON
(B) 2, (B) 13, (B) 22±GROUND : ALWAYS CONTINUITY
(B) 17±GROUND : CONTINUITY WITH PARKING BRAKE LEVER PULLED UP (PARKING BRAKE SW ON)
A 4(B), A 5(C), A 6(A) ABS ACTUATOR
(A) 1, (A) 2±GROUND : APPROX. APPROX. 12 VOLTS
(C) 1±GROUND : ALWAYS CONTINUITY
(B) 1, (B) 5, (B) 4, (B) 6±GROUND : APPROX. 1.15 (IGNITION SW OFF)
(B) 2±GROUND : APPROX. 5 (IGNITION SW OFF)
T3(A), T 4(B) TRACTION BRAKE ACTUATOR
(B) 2± (B) 4 : OPEN ABOVE APPROX. 134.5KG/CM2
(13189 KPA, 1910PSI)
CLOSED BELOW APPROX. 95KG/CM2 (9316 KPA, 1349PSI)
(A) 3± (A) 6 : APPROX. 2
(A) 2± (A) 5 : APPROX. 2
(A) 1± (A) 4 : APPROX. 2
S12 STOP LIGHT SW
2±1 : CLOSED WITH BRAKE PEDAL DEPRESSED
A 7, A 8, A30, A31 ABS SPEED SENSOR FRONT LH, RH, REAR LH, RH
1±2 : APPROX. 1.0(20 °C, 68°F)
T13(B), T14(A) TRACTION ECU
(A) 2±GROUND : APPROX. 12 VOLTS WITH IGNITION SW AT ON POSITION
(A) 15±GROUND : ALWAYS APPROX. 12 VOLTS
(A) 20, (A)14±GROUND : ALWAYS CONTINUITY
(A) 1±GROUND : CONTINUITY WITH PARKING BRAKE LEVER PULLED UP
(B) 2±GROUND : APPROX. 12 VOLTS WITH STOP LIGHT SW ON
(B) 13±GROUND : CONTINUITY WITH TRACTION CUT SW PUSHED ON
(B) 8±GROUND : ALWAYS APPROX. 12 VOLTS
P 3 PARKING BRAKE SW
1±GROUND : CLOSED WITH PARKING BRAKE LEVER PULLED UP
S 8 SUB THROTTLE ACTUATOR
2±1, 2±3 : APPROX. 0.9
5±4, 5±6 : APPROX. 0.9
: PARTS LOCATION
CODESEE PAGECODESEE PAGECODESEE PAGE
A 4B26C 326S 927
A 5C26C13B28S1229
A 6A26C14A28T 227
A 726D 128T 3A27
A 826D 228T 4B27
A1026E 226T 527
A24A28E 326T 629
A25B28E 9A28T1229
A26C28E10B28T13B29
A3030F 926T14A29
A3130P 329
B 126S 827
: RELAY BLOCKS
CODESEE PAGERELAY BLOCKS (RELAY BLOCK LOCATION)
219ENGINE COMPARTMENT LEFT624ENGINE COMPARTMENT LEFT
SERVICE HINTS
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220
COMBINATION METER*1 : W/ TRACTION CONTROL
* 2 : W/O TRACTION CONTROL
2
1
3D
4 3A
6 1E
11
1B5
IK1
12 IK1 11 IK1 13 IK114
IK2
10
OPEN DOOR
RE AR LIGHT
BRAKE
ECT POWER P
R
N
D
C
11 A
17
C
12 A 1A2A 3A4
A
12 B 8
1 2
2 1
EA
10A
DOME
G±O
W±B
W±B
RR
R
G±O
B
GR
R±B
L
G±W
G±W L
R±B
GR
V±R
R±W
V±R
R±W
B
W±B R±W FROM
NEUTRAL START SW
(
A/T )
CLUTCH S TART SW (
M/T )
FROM A/T INDICATOR SW
FROM POWER SOURCE SYSTEM
(
SEE PAGE 56 )
DIODE
(
FOR PARKING
BRAKE )
PARKING
BRAKE SW
COMBINATION METER
P3 D2
C12
,C13 , C1 4
ABC
2
B
4
G±O
FROM ECT PATTERN
SELECT SW
COOLANT LEVEL
TO INTEGRATION
RELAY
BU1
9 B
11
TO LIGHT FAILURE
SENSOR V±G V±G
V±R IE1
1
IG1 20
A
13
R±WI7
I4
2 1
B
DIODE
(
FOR B RAK E
FLUID LEVEL SW )
D1
IG1
19
3E
2
3C
2
R±W
1BRAKE FLUID
LEVEL SW B1 (*2 ) B
IK2
23
R±W R±W
R±W R±W
( CANADA )
(
USA )
R±W
R±W
( USA )
B
(CA NADA )
( *1 )
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26
ELECTRICAL WIRING ROUTING
Position of Parts in Engine Compartment
A 1 A/C Ambient Temp. Sensor E 1 ECT Solenoid
A 2 A/C Lock Sensor and A/C Magnetic Clutch E 2 EFI Water Temp. Sensor
A 3 A/C High Pressure SW E 3 EGR Gas Temp. Sensor (for USA Spec.)
A 4 ABS Actuator E 5 Engine Hood Courtesy SW
A 5 ABS Actuator (w/ Traction Control) E 6 Engine Oil Level Warning SW
A 6 ABS Actuator (w/ Traction Control)
A 7 ABS Speed Sensor Front LH F 1 Front Airbag Sensor LH
A 8 ABS Speed Sensor Front RH F 2 Front Airbag Sensor RH
A 9 Air Flow Meter F 3 Front Clearance Light LH
A 10 Alternator F 4 Front Clearance Light RH
A 11 Alternator F 5Front Side Marker Light LH
A 33 ABS Actuator (w/o Traction Control) F 6 Front Side Marker Light RH F 7 Front Turn Signal Light LH
B 1 Brake Fluid Level SW F 8 Front Turn Signal Light RH
B 6 Back±Up Light SW (for M/T) F 9 Fuse Block
C 3 Check Connector H 1 Headlight Hi LH
C 6 Cornering Light LH H 2 Headlight Hi RH
C 7 Cornering Light RH H 3 Headlight Lo LH
C 8 Cruise Control Actuator H 4 Headlight Lo RH H 5 Horn LH
D 13 Distributor H 6 Horn RH
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27
Position of Parts in Engine Compartment
I 1 ISC Valve S 3Speed Sensor No. 1
I 2 Igniter S 4 Speed Sensor No. 2 (for ECT)
I 4 Ignition Coil S 6 Starter
I 6 Injector No. 1 S 7 Starter
I 7 Injector No. 2 S 8 Sub Throttle Actuator
I 8 Injector No. 3 S 9 Sub Throttle Position Sensor
I 9 Injector No. 4
I 10 Injector No. 5 T 1 Theft Deterrent Horn
I 11 Injector No. 6 T 2 Throttle Position Sensor T 3 Traction Brake Actuator
K 1 Knock Sensor No. 1 (on Front Side) T 4 Traction Brake Actuator
K 2 Knock Sensor No. 2 (on Rear Side) T 5 Traction pump and Motor
N 1 Neutral Start SW, Back±Up Light SW and A/T Indicator SW V 1 VSV (for EGR) (Exc. USA Spec) (for A/T) V 2 VSV (for EVAP)
N 2 Noise Filter (for Defogger System) V 4 VSV (for Water Valve)
N 3 Noise Filter (for Ignition System) V 7 VSV (for Intake Control Valve)
O 2 Oil Pressure SW W 1 Washer Level SW
O 3 Oxygen Sensor Main No. 1 (on Front Side) W 2 Washer Motor
O 4 Oxygen Sensor Main No. 2 (on Rear Side) W 3 Water Temp. Sender W 5 Wiper Motor
P 1 PPS Solenoid
P 20 Power Steering Pressure SW
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