1991 LEXUS SC400 Service Repair Manual

radiator tire type reset infotainment system coolant level child seat sunroof

Page 4057 of 4087

LEXUS SC400 1991 Service Repair Manual
181
THE SRS (SUPPLEMENTAL RESTRAINT SYSTEM) AIRBAG IS A DRIVER PROTECTION DEVICE WHICH HAS A SUPPLEMENTAL ROLE
TO THE SEAT BELTS.
CURRENT FLOWS CONSTANTLY TO TERMINAL 6 OF THE CENTER AIRBAG SENSOR AS

181
THE SRS (SUPPLEMENTAL RESTRAINT SYSTEM) AIRBAG IS A DRIVER PROTECTION DEVICE WHICH HAS A SUPPLEMENTAL ROLE
TO THE SEAT BELTS.
CURRENT FLOWS CONSTANTLY TO TERMINAL 6 OF THE CENTER AIRBAG SENSOR ASSEMBLY. WHEN THE IGNITION SW IS
TURNED TO ACC OR ON, CURRENT FROM THE CIG FUSE FLOWS TO TERMINAL 14 OF THE CENTER AIRBAG SENSOR ASSEMBLY.
ONLY WHEN THE IGNITION SW IS ON DOES THE CURRENT FROM THE IGN FUSE TO TERMINAL 7 .
IF AN ACCIDENT OCCURS WHILE DRIVING, DECELERATION CAUSED BY A FRONTAL IMPACT IS DETECTED BY EACH SENSOR AND
SWITCH, AND WHEN THE FRONTAL IMPACT EXCEEDS A SET LEVEL (WHEN THE SAFING SENSOR BUILT INTO THE CENTER AIRBAG
SENSOR ASSEMBLY IS ON AND THE CENTER AIRBAG SENSOR IS ON, FRONT AIRBAG SENSORS ARE OFF), CURRENT \
FROM THE
CIG OR IGN FUSE FLOWS TO TERMINAL 11 OF THE CENTER AIRBAG SENSOR ASSEMBLY " TERMINAL 1 OF THE AIRBAG SQUIB "
SQUIB " TERMINAL 2 " TERMINAL 10 OF CENTER AIRBAG SENSOR ASSEMBLY " TERMINAL 8, TERMINAL 13 OR BODY GROUND
" GROUND.
WHEN THE SAFING SENSOR BUILT INTO THE CENTER AIRBAG SENSOR ASSEMBLY IS ON AND THE FRONT AIRBAG SENSOR LH OR
RH IS ON, CENTER AIRBAG SENSOR IS OFF AND CURRENT FROM THE CIG OR IGN FUSE FLOWS TO TERMINAL 11 OF THE CENTER
AIRBAG SENSOR ASSEMBLY " TERMINAL 1 OF THE AIRBAG SQUIB " SQUIB " TERMINAL 2 " TERMINAL 10 OF CENTER AIRBAG
SENSOR ASSEMBLY " TERMINAL 3 OR 4 " TERMINAL 1 OF FRONT AIRBAG SENSOR " TERMINAL 2 " TERMINAL 2 OR 5 OF
CENTER AIRBAG SENSOR ASSEMBLY " TERMINAL 8, TERMINAL 13 OR BODY GROUND " GROUND , WHEN THE SAFING SENSOR
BUILT INTO THE CENTER AIRBAG SENSOR ASSEMBLY IS ON, AND THE FRONT AIRBAG SENSOR LH OR RH IS ON AND CENTER
AIRBAG SENSOR IS ON ONE OF THE ABOVE±MENTIONED CIRCUITS IS ACTIVATED SO THAT CURRENT FLOWS TO THE AIRBAG
SQUIB AND CAUSES IT TO OPERATE. THE BAG STORED INSIDE THE STEERING WHEEL PAD IS INSTANTANEOUSLY EXPANDED TO
SOFTEN THE SHOCK TO THE DRIVER.
: PARTS LOCATION
CODESEE PAGECODESEE PAGECODESEE PAGE
A2928C1228T 629
C 326F 126
C1028F 226
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CODESEE PAGEJUNCTION BLOCK AND WIRE HARNESS (CONNECTOR LOCATION)
1E20INSTRUMENT PANEL WIRE
1G20COWL NO. 2 WIRE
1J20COWL WIRE
3A
3B
3D22INSTRUMENT PANEL WIRE
3E
3H
: CONNECTOR JOINING WIRE HARNESS AND WIRE HARNESS
CODESEE PAGEJOINING WIRE HARNESS AND WIRE HARNESS (CONNECTOR LOCATION)
IK136ENGINE WIRE AND INSTRUMENT PANEL WIRE (RIGHT KICK PANEL)
: GROUND POINTS
CODESEE PAGEGROUND POINTS LOCATION
EC34FRONT SIDE OF INTAKE MANIFOLD
ED34REAR SIDE OF CYLINDER HEAD RH
IF36LEFT KICK PANEL
: SPLICE POINTS
CODESEE PAGEWIRE HARNESS WITH SPLICE POINTSCODESEE PAGEWIRE HARNESS WITH SPLICE POINTS
E2034ENGINE WIRE
SYSTEM OUTLINE
WhereEverybodyKnowsYourName

Page 4058 of 4087

LEXUS SC400 1991 Service Repair Manual
182
SRS AIRBAG
WhereEverybodyKnowsYourName

Page 4059 of 4087

LEXUS SC400 1991 Service Repair Manual
62
STARTING AND IGNITION
AM1
AM2
11 4
1
6
ST1
IG2
A
1
B 1 1J
6
1J
7
2
22
1B
4 1K
4
6 9 4 14 13 7 M
IE1
16
EB2
1 IE1
15
E19
L±O
L±O B
B
B WW±R
W± RW
W±L
W±RW±L W
W
B±O
B±W
B
B
B
B
W± R
BATTE

Page 4060 of 4087

LEXUS SC400 1991 Service Repair Manual
63
E18E14
E20
2 1
ED
W± L
B
B±O
B
W± B B±OB±O
B±O
BB
B± O
TO COMBINATION
METER
(
TACHO )12
DISTRIBTOR
IGNITION COIL
I4
D13
IG± TAC +B
IGF IGT C±
IGNITER
CHECK
CONNECTOR
C3 I2
435
19
12
STA I

Page 4061 of 4087

LEXUS SC400 1991 Service Repair Manual
64
STARTING AND IGNITION
C 4 COLD START INJECTOR
2±1 : APPROX. 12 VOLTS WHILE START INJECTOR TIME SW IS CLOSED AND STARTER CRANKING
I15 IGNITION SW
4±1 : CLOSED WITH IGNITION SW AT ST POSITION

Page 4062 of 4087

LEXUS SC400 1991 Service Repair Manual
65
WhereEverybodyKnowsYourName

Page 4063 of 4087

LEXUS SC400 1991 Service Repair Manual
98
STOP LIGHT
1I
10
1C
21E 12
3D
13
1C
10 1H
1 3A
4
1 2
B10 B15
+
±
+
±
BM BL
B15 B14
Bd1
2 Bc1
11
Bd1
1
Bc1
7
7
84
33 4 1
11
1
2
55 1 2
W±B W±B W±B G±W
G±W
W
G±W
G±W
G±W
Y
V±G Y
Y
Y
G±W

Page 4064 of 4087

LEXUS SC400 1991 Service Repair Manual
99
CURRENT IS APPLIED AT ALL TIMES THROUGH A STOP FUSE TO TERMINAL 2 OF THE STOP LIGHT SW.
WHEN THE IGNITION SW IS TURNED ON, CURRENT FLOWS FROM THE GAUGE FUSE TO TERMINAL 8 OF THE LIGHT FAILURE

99
CURRENT IS APPLIED AT ALL TIMES THROUGH A STOP FUSE TO TERMINAL 2 OF THE STOP LIGHT SW.
WHEN THE IGNITION SW IS TURNED ON, CURRENT FLOWS FROM THE GAUGE FUSE TO TERMINAL 8 OF THE LIGHT FAILURE
SENSOR, AND ALSO FLOWS THROUGH THE REAR LIGHT WARNING LIGHT TO TERMINAL 4 OF THE LIGHT FAILURE SENSOR.
STOP LIGHT DISCONNECTION WARNING
WHEN THE IGNITION SW IS TURNED ON AND THE BRAKE PEDAL IS PRESSED (STOP LIGHT SW ON), IF THE STOP LIGHT CIRCUIT IS
OPEN, THE CURRENT FLOWING FROM TERMINAL 7 OF THE LIGHT FAILURE SENSOR TO TERMINALS 1, 2 CHANGES, SO THE LIGHT
FAILURE SENSOR DETECTS THE DISCONNECTION AND THE WARNING CIRCUIT OF THE LIGHT FAILURE SENSOR IS ACTIVATED.
AS A RESULT, THE CURRENT FLOWS FROM TERMINAL 4 OF THE LIGHT FAILURE SENSOR " TERMINAL 11 " GROUND AND TURNS
THE REAR LIGHT WARNING LIGHT ON. BY PRESSING THE BRAKE PEDAL, THE CURRENT FLOWING TO TERMINAL 8 OF THE LIGHT
FAILURE SENSOR KEEPS THE WARNING CIRCUIT ON HOLD AND THE WARNING LIGHT ON UNTIL THE IGNITION SW IS TURNED OFF.
S12 STOP LIGHT SW
2±1: CLOSED WITH BRAKE PEDAL DEPRESSED
L 3 LIGHT FAILURE SENSOR
1, 2, 7±GROUND : APPROX. 12 VOLTS WITH STOP LIGHT SW ON
4, 8±GROUND : APPROX. 12 VOLTS WITH IGNITION SW AT ON POSITION
11±GROUND : ALWAYS CONTINUITY
: PARTS LOCATION
CODESEE PAGECODESEE PAGECODESEE PAGE
C13B28H 930R1131
C14A28L 330S1229
H 830R1031
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CODESEE PAGEJUNCTION BLOCK AND WIRE HARNESS (CONNECTOR LOCATION)
1C20FLOOR WIRE
1E20INSTRUMENT PANEL WIRE
1H20COWL WIRE1I20COWL WIRE
3A22INSTRUMENT PANEL WIRE3D22INSTRUMENT PANEL WIRE
: CONNECTOR JOINING WIRE HARNESS AND WIRE HARNESS
CODESEE PAGEJOINING WIRE HARNESS AND WIRE HARNESS (CONNECTOR LOCATION)
BU140FLOOR WIRE AND INSTRUMENT PANEL WIRE (LEFT KICK PANEL)
Bc140FLOOR NO. 3 WIRE AND FLOOR WIRE (UNDER THE LEFT SIDE OF REAR SEAT CUSHION)
Bd140FLOOR NO. 3 WIRE AND LUGGAGE NO. 2 WIRE (RIGHT SIDE OF LUGGAGE COMPARTMENT)
: GROUND POINTS
CODESEE PAGEGROUND POINTS LOCATION
BL40UNDER THE CENTER PILLAR RH
BM40BACK PANEL CENTER
: SPLICE POINTS
CODESEE PAGEWIRE HARNESS WITH SPLICE POINTSCODESEE PAGEWIRE HARNESS WITH SPLICE POINTS
B1040FLOOR MAIN WIREB1540FLOOR MAIN WIRE
B1440FLOOR MAIN WIREB2140FLOOR NO. 3 WIRE
SYSTEM OUTLINE
SERVICE HINTS
WhereEverybodyKnowsYourName

Load next 8 pages

Page: < prev 1-10 ... 4025-4032 4033-4040 4041-4048 4049-4056 4057-4064 4065-4072 4073-4080 4081-4088 4088 next >

mirror diagram charging clock refrigerant type keyless entry