sensor LEXUS SC400 1991 Service Repair Manual

180
SRS AIRBAG
1G
10 1G 6
1G
11E 13
10 11
IK1
10 IK1 23
IK 1
1
4
+SL
5±SL
3+SR
2±SR
11D+
10D±
13E1
8E2
3E1
3E1
7
IG2 14
ACC 6
+B
12AB 4
TC 11
TC 5
AB
121212 7. 5A
IGN
15A
CIG 15A
ECU±B
FROM ENGINE AND
ECT ECU(
E1 )
CHECK
CONNECTOR
TDCL
FRONT AIRBAG
SENSOR LH FRONT A I RBA G
SENSOR RH
AIRBAG SQUIBSPIRAL
CA BLE
CENTER AIRBAG SENSOR ASSEMBLY
BR
W±B W±BL
Y B
GR
WR
L
Y
B
GR
WR
BR W±B
BR BR BR B±Y P±BP±B
B±Y
P±B
B±Y B±Y W±RW±R
L±R
B±O
FROM POWER SOURCE SYSTEM
(
SEE PAGE 56 )
AIRBA G WA RNING
LIGHT
[COMB. METER]
C10
F1 F2 A2 9 C3
T6 C12
E2 0
1G
9 912
IF ED 1G
7
EC
LA TC
1E
41E 3
3B
2
3H
12
3E
3
3E
10
1J
1 3A
3
1G
4
1G
3 3A
73D 11
B±Y
P±B
B±Y
P±B
B±Y
W±B
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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
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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
G±W B
W±B
R±W
R±W R±W
W±B
W±B
W±B B
FROM POWER SOURCE SYSTEM
(
SEE PAGE 56 )
15A
STOP 10A
GA UGE
A
1
B
11
HOLD
CIRCUIT
W±B
STOP LIGHT
[REAR COMB. LIGHT]
LH RH
R10 R11
HIGH MOUNT STOP
LIGHT
(
W/O REAR SPOILER )
H8
HIGH MOUNT STOP
LIGHT (
W/ REAR SPOILER )
H9
LIGHT FAILURE SENSOR L3 C14 , C1 3
AB
BU1
9
V±G
STOP LIGHT
SW S12
REA R LIGHT WARNING
LIGHT [COMB. METER]
B21
W±B
W±B
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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
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87
EABM
E4 B15 B15
B14
B14
1 2 1
2 1C
21E 12
3D
13 3A
4
B
11 A
1
G
G
W±B GG
W±B W±B
Y
Y
V±G
V±G YY
G
G G
W±B
W±B
W±B
W±B G±R G±R
W±B
W±B W±B G G
911
384
111
255
G±R
W±B FRONT CLEARANCE
LIGHT RH
LIGHT FAILURE
SENSOR
10A
GAUGE
REAR LIGHT
WARNING LIGHT
[COMB. METER]
TAI L LI GHT
[REAR COMB. LIGHT]
LICENCE PLATE
LIGHT
L3
L2
R11
R10
RH
LH FROM POWER SOURCE SYSTEM
(
SEE PAGE 56 )
HOLD
CIRCUIT
BU1
9
C13 ,
C14
B A
+
±
FRONT SI DE M ARK ER
LIGHT RHF6
F4
E1
E1
B
+PK
±PK WRN
W±B
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88
TAILLIGHT
WHEN THE LIGHT CONTROL SW IS TURNED TO TAIL OR HEAD POSITION. THE CURRENT FLOWS TO TERMINAL 3 OF THE LIGHT
FAILURE SENSOR THROUGH THE TAIL FUSE.
WHEN THE IGNITION SW IS TURNED ON, THE 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.
TAILLIGHT DISCONNECTION WARNING
WITH THE IGNITION SW ON AND THE LIGHT CONTROL SW TURNED TO TAIL OR HEAD POSITION. IF THE TAILLIGHT CIRCUIT IS
OPEN, THE LIGHT FAILURE SENSOR DETECTS THE FAILURE BY THE CHANGE IN CURRENT FLOWING FROM TERMINAL 3 OF THE
LIGHT FAILURE SENSOR TO TERMINAL 9, 11 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, WHICH REMAINS ON UNTIL THE LIGHT CONTROL SW IS TURNED O\
FF.
TAILLIGHT RELAY
5±3 : CLOSED WITH LIGHT CONTROL SW AT TAIL OR HEAD POSITION
L 3 LIGHT FAILURE SENSOR
4, 8±GROUND : APPROX. 12 VOLTS WITH IGNITION SW AT ON POSITION
3±GROUND : APPROX. 12 VOLTS WITH LIGHT CONTROL SW AT TAIL OR HEAD POSITION
11±GROUND : ALWAYS CONTINUITY
: PARTS LOCATION
CODESEE PAGECODESEE PAGECODESEE PAGE
C13B28F 526L 230
C14A28F 626L 330
C1528F 926R1031
F 326I16A29 (USA)R1131
F 426I16B29 (CANADA)
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CODESEE PAGEJUNCTION BLOCK AND WIRE HARNESS (CONNECTOR LOCATION)
1A20ENGINE ROOM MAIN WIRE1B20ENGINE ROOM MAIN WIRE
1C20FLOOR WIRE
1E20INSTRUMENT PANEL WIRE
1J20COWL WIRE1K20COWL 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)
: GROUND POINTS
CODESEE PAGEGROUND POINTS LOCATION
EA34FRONT SIDE OF RIGHT FENDER
IF36LEFT KICK PANEL
BM40BACK PANEL CENTER
: SPLICE POINTS
CODESEE PAGEWIRE HARNESS WITH SPLICE POINTSCODESEE PAGEWIRE HARNESS WITH SPLICE POINTS
E 1E1134ENGINE ROOM MAIN WIRE
E 434ENGINE ROOM MAIN WIREB1440FLOOR MAIN WIREE 534ENGINE ROOM MAIN WIREB1540FLOOR MAIN WIRE
SYSTEM OUTLINE
SERVICE HINTS
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