1991 LEXUS SC400 light

SENSOR INSPECTION FOR AIR CONDITIONING SYSTEM ± AC005-04 December 16, 2004
Page 6 of 12
A. Measure the sensor resistance according to the selected graph (specification)\
.
NOTE:
Even slightly touching the sensor may change the resistance value.
Be sure to hold the connector of the sensor.
When measuring, the sensor temperature must be the same as the
ambient temperature.
HINT:
As the temperature increases, the resistance decreases.
Graph 1:
TEMPERATURE 5F ( 5C)SPECIFICATION k W
14 (±10)7.30 to 9.10
23 (±5)5.65 to 6.95
32 (0)4.40 to 5.35
41 (5)3.40 to 4.15
50 (10)2.70 to 3.25
59 (15)2.14 to 2.58
68 (20)1.71 to 2.05
77 (25)1.38 to 1.64
86 (30)1.11 to 1.32
Graph 2:
TEMPERATURE 5F ( 5C)SPECIFICATION k W
14 (±10)7.40 to 9.20
23 (±5)5.65 to 7.00
32 (0)4.35 to 5.40
41 (5)3.40 to 4.20
50 (10)2.68 to 3.30
59 (15)2.10 to 2.60
68 (20)1.66 to 2.10
77 (25)1.32 to 1.66
86 (30)1.05 to 1.35
Inspection
Procedure
(Continued)
Resistance
k W
12.0
3.0
2.0
0.0 32
(0) 68
(20) 104
(40)
Temperature 5F ( 5C)
Max
Min
1.0 4.0 8.0
7.0
5.0 6.0 9.0
10.0 11.0
±4
(±20)
32
(0) 68
(20) 104
(40)
±4
(±20)
Resistance
k W
3.0
2.0
0.0 Temperature 5F ( 5C)
Max
Min
1.0 4.0 8.0
7.0
5.0 6.0 9.0
10.0
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SENSOR INSPECTION FOR AIR CONDITIONING SYSTEM ± AC005-04 December 16, 2004
Page 8 of 12
5. Inspect Solar Sensor.
Four types of solar sensors are used on Lexus vehicles depending on the \
vehicle
specifications. The inspection procedure for each type of sensor differs from the
others. Select the appropriate inspection procedure from the table below\
according to
vehicle specifications and perform the inspection.
EQUIPPED WITH AUTOMATICLIGHT CONTROL SYSTEMA/C SYSTEM WITH RIGHT/LEFT
INDEPENDENT TEMPERATURE CONTROLINSPECTION
PROCEDURE
NoNoA
NoYesB
YesYesC
YesNoD
Procedure A:
a. Disconnect the solar sensor connector.
b. Measure the resistance between terminals 1 and 2 of the solar
sensor under the
following conditions:
Cover the sensor with a cloth
to avoid direct light.
Expose the sensor to light
from a distance of 300 mm
(11.81 in.) or less with an
inspection light.
NOTE:
Terminal 1 of the sensor is always on
the right, when the lock is facing up.
When using an analog tester, connect
the positive (+) lead to terminal 2 and
negative (±) lead to terminal 1 of the
solar sensor.
HINT:
If the light is weak, the sensor may not react. Be sure to use an incand\
escent light for
an inspection light.
Standard:
CONDITIONSPECIFICATION
When the sensor is covered with a cloth
(to avoid direct light)Infinite ohms
When the sensor is exposed to lightLess than infinite resistance
InspectionProcedure
(Continued)
Lock
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SENSOR INSPECTION FOR AIR CONDITIONING SYSTEM ± AC005-04 December 16, 2004
Page 9 of 12
Procedure B:
a. Disconnect the solar sensor connector.
b. Measure the resistance between terminals 2 and 3 of the solar
sensor under the
following conditions:
Cover the sensor with a cloth
to avoid direct light.
Expose the sensor to light
from a distance of 300 mm
(11.81 in.) or less with an
inspection light.
NOTE:
When using an analog tester, connect
the positive (+) lead to terminal 3 and
negative (±) lead to terminal 2 of the
solar sensor.
HINT:
If the light is weak, the sensor may not react. Be sure to use an incand\
escent light for
an inspection light.
Standard:
CONDITIONSPECIFICATION
When the sensor is covered with a cloth
(to avoid direct light)Infinite ohms
When the sensor is exposed to lightLess than infinite resistance
InspectionProcedure
(Continued)
Lock
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SENSOR INSPECTION FOR AIR CONDITIONING SYSTEM ± AC005-04 December 16, 2004
Page 10 of 12
Procedure C:
a. Turn the ignition switch ON.
b. Measure the voltage between terminals TSR (+) and CLTE (±)
of the connector under the
following conditions:
Cover the sensor with a cloth
to avoid direct light.
Expose the sensor to light
from a distance of 300 mm
(11.81 in.) or less with an
inspection light.
HINT:
If the light is weak, the sensor may not react. Be sure to use an incandes\
cent light
for an inspection light.
Do not disconnect the solar sensor connector.
Standard:
CONDITIONSPECIFICATION
When the sensor is covered with a cloth
(to avoid direct light)Below 0.8 V
When the sensor is exposed to light4.3 +/± 0.3 V
c. Measure the voltage between
terminals TSL (+) and CLTE (±)
of the connector under the
following conditions:
Cover the sensor with a cloth
to avoid direct light.
Expose the sensor to light
from a distance of 300 mm
(11.81 in.) or less with an
inspection light.
HINT:
If the light is weak, the sensor may not react. Be sure to use an incand\
escent light
for an inspection light.
Do not disconnect the solar sensor connector.
Standard:
CONDITIONSPECIFICATION
When the sensor is covered with a cloth
(to avoid direct light)Below 0.8 V
When the sensor is exposed to light4.3 +/± 0.3 V
InspectionProcedure
(Continued)
CLTE
TSR
TSL
CLTE
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SENSOR INSPECTION FOR AIR CONDITIONING SYSTEM ± AC005-04 December 16, 2004
Page 11 of 12
Procedure D:
a. Turn the ignition switch ON.
b. Using the tester, measure the voltage between terminals
TSD (+) and CLTE (±) of the
connector under the
following conditions:
Cover the sensor with a cloth
to avoid direct light.
Expose the sensor to light
from a distance of 300 mm
(11.81 in.) or less with an
inspection light.
HINT:
If the light is weak, the sensor may not react. Be sure to use an incandes\
cent light
for an inspection light.
Do not disconnect the solar sensor connector.
Standard:
CONDITIONSPECIFICATION
When the sensor is covered with a cloth
(to avoid direct light)Below 0.8 V
When the sensor is exposed to light4.3 +/± 0.3 V
InspectionProcedure
(Continued)
TSD
CLTE
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Some SC 300/SC 400 vehicles may have a sunvisor which falls away slightly from the roof
when placed in the full upright position. To improve visor retention, the position of an internal
clip has been modified in production.
BODY
BO92±004
APRIL 24, 1992
SC 300/SC 400
PART NUMBER INFORMATION:
New Part NumberPrev. Part NumberDescriptionSide
NOTE:Before replacing the Sunvisor assembly, ensure that shaft is fully seated into the
sunvisor by pushing the sunvisor further onto the shaft. This may
seat the internal clip into
the groove on the shaft.
PRODUCTION EFFECTIVE:
FROM: November, 1991
VIN: SC 400: JT8UZ30C9N0011202
SC 300: JT8JZ30C9N0002890
Same
º
º
Same
º
º
Same
º
º
Same
º
º Medium Gray
SpruceIvory
SC 300/SC 400 IMPROVED SUNVISOR HINGE RETENTION (REVISED) Page 1 of 1
Medium Gray
SpruceIvory
Medium Gray SpruceIvory
Medium Gray SpruceIvory RH
RH
RH
RH w/Sunroof
RH w/Sunroof
RH w/Sunroof LH
LH
LH
LH w/Sunroof
LH w/Sunroof
LH w/Sunroof
74310±24120±03
74310±24120±07
74310±24120±08
74310±24130±03
74310±24130±07
74310±24130±08
74320±24130±03
74320±24130±07
74320±24130±08
74320±24080±03
74320±24080±07
74320±24080±08
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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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