LEXUS SC400 1991 Service Repair Manual

120
WIRELESS DOOR LOCK REMOTE CONTROL
DOOR LOCK CONTROL (LOCK AND UNLOCK) IS PERFORMED BY REMOTE CONTROL, WI\
THOUT THE IGNITION KEY INSERTED IN
THE DOOR KEY CYLINDER, USING LOW±POWER RADIO WAVES EMITTED BY A TRANSMITTER BUILT INTO IGNITION KEY.
1. WIRELESS DOOR LOCK OR UNLOCK NORMAL OPERATION
WITH THE WIRELESS DOOR LOCK MAIN SW ON, THE IGNITION KEY NOT INSERTED INTO THE IGNITION KEY CYLINDER (UNLOCK
WARNING SW OFF) AND ALL THE DOORS COMPLETELY CLOSED, WHEN THE SWITCH (TRANSMITTER) ON THE IGNITION KEY IS
PUSHED, THE WIRELESS DOOR LOCK ECU RECEIVES THE ELECTRICAL WAVES FROM THE IGNITION KEY (TRANSMITTER),
CAUSING IT TO OPERATE.
AS A RESULT, THE ECU JUDGES WHETHER THE DOOR IS LOCKED OR UNLOCKED BASED ON THE SIGNAL FROM THE DOOR LOCK
MOTOR, AND SENDS A SIGNAL TO THE DOOR LOCK ECU TO SWITCH THE CONDITION FROM LOCK TO UNLOCK OR VICE VERSA,
CAUSING THE DOOR LOCK MOTOR TO OPERATE (FOR THE CURRENT FLOW DURING LOCK AND UNLOCK REFER TO THE DOOR
LOCK CONTROL SYSTEM.)
2. AUTO LOCK OPERATION
AFTER PUSHING THE IGNITION KEY SWITCH (TRANSMITTER) TO UNLOCK ALL THE DOORS, IF A DOOR IS NOT OPENED WITHIN 30
SECONDS, ALL OF THE DOORS ARE AUTOMATICALLY LOCKED AGAIN.
3. WIRELESS DOOR LOCK STOP FUNCTION
IF A DOOR IS OPEN (DOOR COURTESY SW ON), A SIGNAL IS INPUT FROM THE DOOR OPEN COURTESY SW TO THE WIRELESS
DOOR LOCK ECU, STOPPING WIRELESS DOOR LOCK OR UNLOCK.
IF THE IGNITION KEY IS IN THE IGNITION KEY CYLINDER (UNLOCK WARNING SW ON), THE UNLOCK WARNING SWITCH INPUT A
SIGNAL TO THE WIRELESS DOOR LOCK ECU, STOPPING WIRELESS DOOR LOCK OR UNLOCK.
4. DOOR LOCK MOTOR PROTECTIVE FUNCTION
IF THE DOOR LOCK OR UNLOCK CONDITION DOES NOT CHANGE AFTER WIRELESS DOOR L\
OCK OR UNLOCK OPERATION, THE
DOOR LOCK ECU SENDS CURRENT TEN TIMES TO THE DOOR LOCK MOTOR. IF THE DOOR LOCK CONDITION STILL HAS NOT
CHANGED AS A RESULT THE WIRELESS DOOR LOCK ECU STOPS RECEPTION AND STOPS DOOR LOCK AND UNLOCK FUNCTION.
BY MANUALLY OPERATION THE DOOR LOCK OR UNLOCK, THE STOP CONDITION OF THE WIRELESS DOOR LOCK FUNCTION IS
RELEASED.
D10, D11 DOOR OPEN DETECTION SW LH, RH
3±6 : CLOSED WITH DOOR OPENED
I15 UNLOCK WARNING SW [IGNITION SW]
10±9 : CLOSED WITH IGNITION KEY IN CYLINDER
W 8 WIRELESS DOOR LOCK ECU
1±GROUND: APPROX. 12 VOLTS WITH WIRELESS DOOR LOCK MAIN SW ON
7±GROUND: ALWAYS CONTINUITY
10±GROUND: CONTINUITY WITH EACH DOOR OPENED
6±GROUND: CONTINUITY WITH IGNITION KEY IN CYLINDER
: PARTS LOCATION
CODESEE PAGECODESEE PAGECODESEE PAGE
D1030I1529W 729
D1130T 929W 831
: RELAY BLOCKS
CODESEE PAGERELAY BLOCKS (RELAY BLOCK LOCATION)
219ENGINE COMPARTMENT LEFT
423LEFT 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 WIRE3E22INSTRUMENT PANEL WIRE
SYSTEM OUTLINE
SERVICE HINTS
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: CONNECTOR JOINING WIRE HARNESS AND WIRE HARNESS
CODESEE PAGEJOINING WIRE HARNESS AND WIRE HARNESS (CONNECTOR LOCATION)
IF236FRONT DOOR LH WIRE AND COWL WIRE (LEFT KICK PANEL)
IP138FRONT DOOR RH WIRE AND COWL WIRE (RIGHT KICK PANEL)
BX140FLOOR NO. 3 WIRE AND COWL WIRE (RIGHT KICK PANEL)
BY140INSTRUMENT PANEL WIRE AND FLOOR NO. 3 WIRE (RIGHT KICK PANEL)
: GROUND POINTS
CODESEE PAGEGROUND POINTS LOCATION
IF36LEFT KICK PANEL
IJ36RIGHT KICK PANEL
BL40UNDER THE CENTER PILLAR RH
: SPLICE POINTS
CODESEE PAGEWIRE HARNESS WITH SPLICE POINTSCODESEE PAGEWIRE HARNESS WITH SPLICE POINTS
I 2B 440FRONT DOOR LH WIREI 7B 540FRONT DOOR LH WIRE
I 838COWL WIREB 640FRONT DOOR RH WIREI11
COWL WIRE
B 740FRONT DOOR RH WIRE
I15
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WIPER AND WASHER
: PARTS LOCATION
CODESEE PAGECODESEE PAGECODESEE PAGE
C15B28W 227
C16A28W 527
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CODESEE PAGEJUNCTION BLOCK AND WIRE HARNESS (CONNECTOR LOCATION)
1H
1J20COWL WIRE
1K
: CONNECTOR JOINING WIRE HARNESS AND WIRE HARNESS
CODESEE PAGEJOINING WIRE HARNESS AND WIRE HARNESS (CONNECTOR LOCATION)
IE136ENGINE ROOM MAIN WIRE AND COWL WIRE (R/B NO. 4)
: GROUND POINTS
CODESEE PAGEGROUND POINTS LOCATION
IF36LEFT KICK PANEL
: SPLICE POINTS
CODESEE PAGEWIRE HARNESS WITH SPLICE POINTSCODESEE PAGEWIRE HARNESS WITH SPLICE POINTS
I 738COWL WIRE
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WIPER AND WASHER
IFM
1 2
M 1
23 6 5
+1 B +S
+2
OFF
INT
LOW/MIST
HIGH
WASHER
INT TIME
IE1
4
A
13
A7
A
14 B
17
B8
A
6 IE 1
3
1K
6
1J
1 1H
16
L
R±L L±R
L±W
W±B
G±O L
R±L G±O
L
L
L
L
L±R
L
L±W
W±B
W±B
W±B
WIPER AND WASHER SW
(
W/ WIPER RELAY )
[COMB. SW] FROM POWER SOURCE SYSTEM
(
SEE PAGE 56 )
20A
WIPER
WIPER MOTOR W5
C15 , C 1 6
BA
WASHER
MOTOR W2
WIPER RELAY I7
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WITH THE IGNITION SW TURNED ON, THE CURRENT FLOWS TO TERMINAL (A)14 OF THE WIPER AND WASHER SW, TERMINAL 2 OF
THE WASHER MOTOR AND TERMINAL 6 OF THE WIPER MOTOR THROUGH THE WIPER FUSE.
1. LOW SPEED POSITION
WITH WIPER SW TURNED TO LOW POSITION, THE CURRENT FLOWS FROM TERMINAL (A)14 OF THE WIPER AND WASHER SW "
TERMINAL (B)8 " TERMINAL 3 OF THE WIPER MOTOR " TERMINAL 1 " TO GROUND AND CAUSES TO THE WIPER MOTOR TO RUN
AT LOW SPEED.
2. HIGH SPEED POSITION
WITH WIPER SW TURNED TO HIGH POSITION, THE CURRENT FLOWS FROM TERMINAL (A)14 OF THE WIPER AND WASHER SW "
TERMINAL (A)7 " TERMINAL 2 OF THE WIPER MOTOR " TERMINAL 1 " TO GROUND AND CAUSES TO THE WIPER MOTOR TO RUN
AT HIGH SPEED.
3. INT POSITION
WITH WIPER SW TURNED TO INT POSITION, THE RELAY OPERATES AND THE CURRENT WHICH IS CONNECTED BY RELAY
FUNCTION FLOWS FROM TERMINAL (A)14 OF THE WIPER AND WASHER SW " TERMINAL (A)6 " TO GROUND . THIS FLOW OF
CURRENT OPERATES THE INTERMITTENT CIRCUIT AND THE CURRENT FLOWS FROM TERMINAL (A)14 OF THE WIPER AND
WASHER SW " TERMINAL (B)8 " TERMINAL 3 OF THE WIPER MOTOR " TERMINAL 1 " TO GROUND AND FUNCTIONS.
THE INTERMITTENT OPERATION IS CONTROLLED BY A CONDENSER'S CHARGED AND DISCHARGED FUNCTION INST\
ALLED IN
RELAY AND THE INTERMITTENT TIME IS CONTROLLED BY A TIME CONTROL SW TO CHARGE THE CHARGING TIME OF THE
CONDENSER.
4. MIST POSITION
WITH WIPER SW TURNED TO MIST POSITION, THE CURRENT FLOWS FROM TERMINAL (A)14 OF THE WIPER AND WASHER SW "
TERMINAL (B)8 " TERMINAL 3 OF THE WIPER MOTOR " TERMINAL 1 " TO GROUND AND CAUSES TO THE WIPER MOTOR TO RUN
AT LOW SPEED.
5. WASHER CONTINUOUS OPERATION
WITH WASHER SW TURNED TO ON, THE CURRENT FLOWS FROM TERMINAL 2 OF THE WASHER MOTOR " TERMINAL 1 "
TERMINAL (A)13 OF THE WIPER AND WASHER SW " TERMINAL (A)6 " TO GROUND AND CAUSES TO THE WASHER MOTOR TO
RUN. AND WINDOW WASHER IS JET. THIS CAUSES THE CURRENT TO FLOW WASHER CONTINUOUS OPERATION CIRCUIT IN
TERMINAL (A)14 OF THE WIPER AND WASHER SW " TERMINAL (B)8 " TERMINAL 3 OF THE WIPER MOTOR " TERMINAL 1 TO
GROUND AND FUNCTION.
C15(B), C16(A) WIPER AND WASHER SW [COMB. SW]
(A) 6±GROUND : ALWAYS CONTINUITY
(A) 14±GROUND : APPROX. 12 VOLTS WITH IGNITION SW AT ON POSITION
(B) 8±GROUND : APPROX. 12 VOLTS WITH WIPER AND WASHER SW AT LOW OR MIST POSITION
APPROX. 12 VOLTS EVERY APPROX. 1 TO 10 SECONDS INTERMITTENTLY WITH WIPER SW AT INT POSITION
(B) 17±GROUND : APPROX. 12 VOLTS WITH IGNITION SW ON UNLESS WIPER MOTOR AT STOP POSITION
(A) 7±GROUND : APPROX. 12 VOLTS WITH IGNITION SW ON AND AFTER WIPER SW OFF UNTIL WIPER MOTOR STOPS
W 5 WIPER MOTOR
6±5 : CLOSED UNLESS WIPER MOTOR AT STOP POSITION
SYSTEM OUTLINE
SERVICE HINTS
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ABBREVIATIONS
DISCONNECTION AND CONNECTION OF BOLT
TYPE CONNECTORS
For engine and ECT ECU in this vehicle, connectors are used
which require a bolt built into the connector to be screwed down to
securely connect the connector.
1. Disconnect the connectorAfter completely loosening the bolt, the two parts of the
connector can be separated.
NOTICE:
Do not pull the wire harness when disconnecting the
connector.
2. Connect the connector
NOTICE:
Before connecting the connector, always check that the
terminals are not bent or damaged.
(a) Match the guide section of the male connectorcorrectly with the female connector, then press them
together.
(b) Tighten the bolt. Make sure the connectors are completely connected,
by tightening the bolt until there is a clearance of less
than 1 mm (0.04 in.) between the bottom of male
connector and the end of female connector.
ABBREVIATIONS
The following abbreviations are used in this manual.
A/C = Air Conditioning O/D = Overdrive
ABS = Anti±Lock Brake System R/B = Relay Block
A/T = Automatic Transmission RH = Right±Hand
CB = Circuit Breaker SRS = Supplement Restraint System
COMB. = Combination SW = Switch
ECT = Electronic Controlled Transmission TDCL = Total Diagnostic Communication Link
ECU = Electronic Control Unit TEMP. = Temperature
EGR = Exhaust Gas Recirculation TRAC = Traction Control
FL = Fusible Link VSV = Vacuum Switching Valve
ISC = Idle Speed Control W/ = With
J/B = Junction Block W/O = Without
LH = Left-Hand
* The titles given inside the components are the names of the terminals (ter\
minal codes) and are not treatedas being abbreviations.
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ABS (ANTI±LOCK BRAKE SYSTEM)
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ABS (ANTI±LOCK BRAKE SYSTEM)
M
A
11
MR A
4
R± A
5
SR
A
6 SFL
A
12 SRR
A
8 AST
A
9 MT
B
1 SFR
B
16 PKB
B
2 GND
B
13 GND
B
1B 4 B
3B 2B5
A 4
A 3
A 1 2 1
IG1
19
IO1
5IO1 7
EB EA 16 22 23 11
EB1
6IK1 10
IJ
EA 1
34
3 2
16
1
4
2
IK2
25 IK2 2
IE1
1
IE2
12
2 1
E10
I23I25
E9
2
6 6
666
66
66
6
B
10
WA
B
6
TS
5
6
E12 L
P±B
V±Y
L±W
L±W L
W
V±YL
W± B L±W V±YY±L
R
R
R
B±R
B±R
B±R
P±B
V
L
L
L V
L V±Y
V
R±Y
Y
B±Y P
L±W Y±G
R±W R±W
W±B
W±B
R±W
R±W
B
B
W±B
W±B W±B
W±B W±B
L±WL
W± B
SFR SFL SRR AST MT
BS
BM
GND WA
TS TC
WB
BATTERY ABS ECU
(
W/O TRACTION CONTROL )
R
120A ALT
60A ABS NO. 1
ABS MOTOR
RELAY
ABS ACTUATOR
RELAY
CHECK
CONNECTOR
FUSE BLOCK
R±W
DIODE
(FOR PARKING BRAKE )
BRAKE FLUID
LEVEL SW
PARKING
BRAKE
SW
ABS ACTUATOR
(
CANA DA )
( USA )
B1
D2
A4 , A33
P3
A2 2
,A23
B
BA A
C3
F9 SHORT PIN
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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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