1991 LEXUS SC400 brake

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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223
COMBINATION METER
B 1 BRAKE FLUID LEVEL SW
1±2 : CLOSED WITH FLOAT DOWN
P 3 PARKING BRAKE SW
1±GROUND : CLOSED WITH PARKING BRAKE LEVER PULLED UP
O 2 OIL PRESSURE SW
1±GROUND : CLOSED WITH OIL PRESSURE BELOW APPROX. 0.2 KG/CM2 (2.8 PSI, 20 KPA)
W 3 WATER TEMP. SENDER
1±GROUND : APPROX. 226
(50 °C, 122 °F)
APPROX. 25
(11 5 °C, 239 °F)
E 6 ENGINE OIL LEVEL WARNING SW
1±2 : CLOSED WITH FLOAT UP AND ENGINE OIL TEMP. AT BELOW APPROX. 55°C ( 131 °F)
OPEN WITH FLOAT DOWN AND ENGINE OIL TEMP. AT BELOW APPROX. 60°C ( 140 °F)
F18(A) FUEL SENDER
2±3 : APPROX. 3
AT FUEL FULL
APPROX. 11 0
AT FUEL EMPTY
C14 (C) COMBINATION METER
1±GROUND : APPROX. 12 VOLTS WITH IGNITION SW AT ON POSITION
12±GROUND : APPROX. 12 VOLTS WITH IGNITION SW AT ST POSITION AND SHIFT LEVER AT P OR N RANGE
10±GROUND : ALWAYS CONTINUITY
22±GROUND : ALWAYS CONTINUITY
11±GROUND : ALWAYS APPROX. 12 VOLTS
: PARTS LOCATION
CODESEE PAGECODESEE PAGECODESEE PAGE
A1026E 626R 929
B 126F17B30S 327
C12A28F18A30S22B29
C13B28I 227S23A29
C14C28I16A29T1529
D 128O 227W 127
D 228P 329W 327
: RELAY BLOCKS
CODESEE PAGERELAY BLOCKS (RELAY BLOCK LOCATION)
219ENGINE COMPARTMENT LEFT
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CODESEE PAGEJUNCTION BLOCK AND WIRE HARNESS (CONNECTOR LOCATION)
1B20ENGINE ROOM MAIN WIRE
IE20INSTRUMENT PANEL WIRE
1G20COWL NO. 2 WIRE
1H
1I20COWL WIRE1J20COWL WIRE
1K
3A
3B
3C
3D22INSTRUMENT PANEL WIRE
3E
3F
3H
SERVICE HINTS
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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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28
ELECTRICAL WIRING ROUTING
Position of Parts in Instrument Panel
A 12 A/C Control Assembly C 9 CD Player
A 13 A/C Control Assembly C 10 Center Airbag Sensor Assembly
A 14 A/C Control Assembly C 11 Cigarette Lighter
A 15 A/C Control SW and Radio SW C 12 Combination Meter
A 16 A/C Evaporator Temp. Sensor C 13 Combination Meter
A 17 A/C Power Transistor C 14Combination Meter
A 18 A/C Power Transistor C 15 Combination SW
A 19 A/C Room Temp. Sensor C 16 Combination SW
A 20 A/C Solar Sensor C 17 Combination SW
A 21 A/T Indicator Light (for Shift Lever) C 19 Cruise Control ECU
A 22 ABS ECU (for M/T, w/o Traction Control) C 23 Clutch Start SW
A 23 ABS ECU (for M/T, w/o Traction Control) C 24 Cruise Control Clutch SW
A 24 ABS and Traction ECU
A 25 ABS and Traction ECU D 1 Diode (for Brake Fluid Level)
A 26 ABS and Traction ECU D 2 Diode (for Parking Brake)
A 27 Air Mix Control Servo Motor D 3 Diode (for Tension Reduser)
A 28 Air Vent Mode Control Servo Motor
A 29 Airbag Squib E 8 ECT Pattern Select SW
A 33 Air Inlet Control Servo Motor E 9 Engine and ECT ECU (for A/T) E 10 Engine and ECT ECU (for A/T)
B 2 Blower Motor E 11 Engine ECU (for M/T)
B 3 Blower Resistor (for Low Speed) E 12 Engine ECU (for M/T)
F 10 Fuel Lid Opener SW
G 1 Glove Box Light
G 2 Glove Box Light SW
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29
Position of Parts in Instrument Panel
H 7 Hazard SW S 10 Shift Lock ECUS 11 Step Light
I 14 Ignition Key Cylinder Light S 12 Stop Light SW
I 15 Ignition SW, Unlock Warning SW and Key Inter Lock Solenoid S 22 Short Connector
I 16 Integration Relay S 23 Short Connector S 24 Seat Heater SW (for M/T)
K 3 Kick Down SW T 6 TDCL (Total Diagnostic Communication Link)
L 1 Luggage Compartment Door Open SW T 7 Telescopic Position Sensor T 8 Theft Deterrent and Door Lock Control ECU
N 4 Noise Filter (for A/C System) T 9 Theft Deterrent and Door Lock Control ECU T 10 Tilt and Power Telescopic ECU
O 5 O/D Main SW T 11 Tilt and Power Telescopic ECU T 12 Traction Cut SW and Seat Heater SW (for A/T)
P 2 PPS ECU T 13 Traction ECU (for A/T)
P 3 Parking Brake SW T 14 Traction ECU (for A/T) T 15 Trip SW and Theft Deterrent Indicator Light
R 2 Radio and Player
R 3 Radio and Player W 6 Water Temp. Sensor (for A/C System)
R 4 Radio and Player (w/ CD Player) W 7 Wireless Door Lock Main SW
R 5 Radio and Player (w/o CD Player)
R 6 Radio and Player (w/o CD Player)
R 7 Remote Control Mirror ECU
R 8 Remote Control Mirror ECU
R 9 Rheostat
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149
1K
4 1I
10
B
9B 64 A 12
1
IJ2
2IJ2 1IJ1
6
PARKING
BRAKE SWM42
4 31
5
7
6
23
1 25A
STOP
7. 5A
ST
POTENTIO METER
CRUIS E CONTROL ACTUATOR GN DL
MC
MO
VR3
VR2
VR1
MAGNETIC
CLUTCH
S2 IDL1 OD1
ECT IDL OD VR1 VR2 VR3 MC MO L STP±
N& C STP+
CRUISE CONTROL ECU
STOP
LIGHT
SW
B±W B±W
W
B±W
W
W
G±W BR±Y
R
W±R
W±R
R
BR±Y
R±B
LG±R P
LG
G±R
W
R±L R±B
LG±R P
LG
G±R B±W
W±B
I9
S12
C19
P3C8
FROM POWER SOURCE SYSTEM
(
SEE PAGE 56 )
R±W
B
PKB
ENGINE AND ECT ECU E9 ,E10
I7
EA
IE 2
10
IE2
11
IE2
5
IE2
1
IE2
6
IE2
2
IG1
19
IJ2
9
B (
CANA DA )
(
USA )
R±L
22 23 9 3 24 25 26 12 11 10 16 1
A B IJ2
10
I9
C24 C23
CLUTCH
START SW CRUISE
CONTROL
CLUTCH SW(
A/T )
B±W
BB±W
B±W
B±W
(
A/T )
(
A/T )
1
2
2
21
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150
CRUISE CONTROL
CURRENT IS APPLIED AT ALL TIMES THROUGH STOP FUSE TO TERMINAL 1 OF THE CONTROL ECU TERMINAL 2 OF STOP LIGHT
SWITCH, AND ALSO THROUGH THE DOME FUSE TO TERMINAL 15 OF CRUISE CONTROL ECU.
WITH THE IGNITION SWITCH TURNED TO ON, THE CURRENT FLOWS THROUGH GAUGE FUSE TO TERMINAL (A)1 OF COMBINATION
METER AND THE CURRENT THROUGH ECU±IG FUSE FLOWS TO TERMINAL 14 OF CRUISE CONTROL ECU.
WHEN THE IGNITION SWITCH IS ON AND THE CRUISE CONTROL MAIN SWITCH IS TUR\
NED ON, A SIGNAL IS INPUT FROM TERMINAL
15 OF CRUISE CONTROL MAIN SWITCH TO TERMINAL 4 OF CRUISE CONTROL ECU. AS A RESULT, THE CRUISE CONTROL ECU
FUNCTIONS AND THE CURRENT TO TERMINAL 14 OF CRUISE CONTROL ECU TO TERMINAL 13 OF CRUISE CONTROL ECU "
GROUND, AND THE CRUISE CONTROL SYSTEM IS IN A CONDITION READY FOR OPERATION.
AT THE SAME TIME, THE CURRENT THROUGH THE GAUGE FUSE FLOWS FROM TERMINAL (A)1 OF CRUISE CONTROL INDICATOR
LIGHT " TERMINAL (B)20 "TERMINAL 5 OF CRUISE CONTROL ECU "TERMINAL 13 " TO GROUND, CAUSING THE CRUISE
CONTROL INDICATOR LIGHT TO LIGHT UP, INDICATING THAT THE CRUISE CONTROL IS READY FOR OPERATION.
1. SET OPERATION
WHEN THE CRUISE CONTROL MAIN SWITCH IS TURNED ON AND THE SET SWITCH IS PUSHE\
D WITH THE VEHICLE SPEED WITHIN
THE SET LIMIT (APPROX. 40 KM/H, 2.5 MPH TO 200 KM/H, 124 MPH), A SIGNAL IS INPUT TO TERMINAL 18 OF THE CRUISE CONTROL
ECU AND THE VEHICLE SPEED AT THE TIME THE SET SWITCH IS RELEASED IS MEMORIZED IN THE ECU AS THE SET\
SPEED.
2. SET SPEED CONTROL
DURING CRUISE CONTROL DRIVING, THE ECU COMPARES THE SET SPEED MEMORIZED IN THE ECU WITH THE ACTUAL VEHICLE
SPEED INPUT INTO TERMINAL 20 OF THE CRUISE CONTROL ECU FROM THE SPEED SENSOR, AND CONTROLS THE CRUIS\
E
CONTROL ACTUATOR TO MAINTAIN THE SET SPEED.
WHEN THE ACTUAL SPEED IS LOWER THAN THE SET SPEED, THE ECU CAUSES THE CURREN\
T TO THE CRUISE CONTROL
ACTUATOR TO FLOW FROM TERMINAL 12 " TERMINAL 6 OF CRUISE CONTROL ACTUATOR "TERMINAL 7 " TERMINAL 11 OF
CRUISE CONTROL ECU. AS A RESULT, THE MOTOR IN THE CRUISE CONTROL ACTUATOR IS ROTATED TO OPEN THE THROTTLE
VALVE AND THE THROTTLE CABLE IS PULLED TO INCREASE THE VEHICLE SPEED. WHEN THE ACTUAL DRIVING SPEED IS HIGHER
THAN THE SET SPEED, THE CURRENT TO CRUISE CONTROL ACTUATOR FLOWS FROM TERMINAL 11 OF ECU "TERMINAL 7 OF
CRUISE CONTROL ACTUATOR "TERMINAL 6 "TERMINAL 12 OF CRUISE CONTROL ECU.
THIS CAUSES THE MOTOR IN THE CRUISE CONTROL ACTUATOR TO ROTATE TO CLOSE THE THROTTLE VALVE AND RETURN THE
THROTTLE CABLE TO DECREASE THE VEHICLE SPEED.
3. COAST CONTROL
DURING THE CRUISE CONTROL DRIVING, WHILE THE COAST SWITCH IS ON, THE CRUISE CONTROL ACTUATOR RETURNS THE
THROTTLE CABLE TO CLOSE THE THROTTLE VALVE AND DECREASE THE DRIVING SPEED. THE VEHICLE SPEED WHEN THE COAST
SWITCH IS TURNED OFF IS MEMORIZED AND THE VEHICLE CONTINUES AT THE NEW SET SPEED.
4. ACCEL CONTROL
DURING CRUISE CONTROL DRIVING, WHILE THE ACCEL SWITCH IS TURNED ON, THE CRUISE\
CONTROL ACTUATOR PULLS THE
THROTTLE CABLE TO OPEN THE THROTTLE VALVE AND INCREASE THE DRIVING SPEED.
THE VEHICLE SPEED WHEN THE ACCEL SWITCH IS TURNED OFF IS MEMORIZED AND THE \
VEHICLE CONTINUES AT THE NEW SET
SPEED.
5. RESUME CONTROL
UNLESS THE VEHICLE SPEED FALLS BELOW THE MINIMUM SPEED LIMIT (APPROX. 40 KM/H, 25 MPH) AFTER CANCELING THE SET
SPEED BY THE CANCEL SWITCH, PUSHING THE RESUME SWITCH WILL CAUSE THE VEHICLE \
TO RESUME THE SPEED SET BEFORE
CANCELLATION.
6. MANUAL CANCEL MECHANISM
IF ANY OF THE FOLLOWING OPERATIONS OCCURS DURING CRUISE CONTROL OPERATION, THE SAFETY MAGNETIC CLUTCH OF
THE ACTUATOR TURNS OFF AND THE MOTOR ROTATES TO CLOSE THE THROTTLE VALVE AND THE CRUISE CONTROL IS
RELEASED.
* PLACING THE SHIFT LEVER IN ªNº RANGE (NEUTRAL START SWITCH ON)). ªSIGNAL INPUT TO TERMINAL 2 OF ECUº
* DEPRESSING THE BRAKE LEVER (STOP LIGHT SWITCH ON). ªSIGNAL INPUT TO TERMINAL 16 OF ECUº
* PULLING THE PARKING BRAKE PEDAL (PARKING BRAKE SWITCH ON). ªSIGNAL INPUT TO TERMINAL 3 OF ECUº
* PUSHING THE CANCEL SWITCH (CANCEL SWITCH ON). ªSIGNAL INPUT TO TERMINAL 18ª
SYSTEM OUTLINE
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