LEXUS SC400 1991 Service Repair Manual

AIR CONDITIONING EVAPORATOR ODOR ± AC001±97 September 12, 1997
GS 3003. Reinstallation of parts.
(Continued) (a) Insert the (2) filters into the cooling
unit as shown in the illustration.
NOTE:
Insert a clean air filter with it's knob
facing downwards, then slide it forward
and install the second filter in the same
manner.
(b) Assemble the rubber insulator on the plate.
CAUTION:
To prevent the cooling unit from leaking
water, pull the three rubber projections
from the other side of the plate to make
sure that the rubber insulator seals
properly against the plate.
(c) Install the plate on the cooling unit and secure with the (2) wing nuts.
CAUTION:
To prevent water leaks, verify that the
cooling unit and plate are fully secure
before tightening the wing nuts.
NOTE:
Before installing the plate on the cooling
unit, coat the rubber insulator with water
for easier assembly.
(d) Reinstall the lamp.
(e) Reassemble the Undercover.
Page 6 of 11
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Page 7 of 11
AIR CONDITIONING EVAPORATOR ODOR ± AC001±97 September 12, 1997
LS 4001. Removal of parts.
('93±'94) (a) Remove the undercover.
NOTE:
Remove the front of ªAº clips.
Pull down the three ªBº clip areas
of the Undercover to remove.
(b) Remove the lamp.
(c) Remove the (2) wing nuts and the plate on the bottom of the cooling unit.
CAUTION:
The plate and wing nuts will be reused.
(d) Remove the (2) filters from the cooling unit.
2. Clean the Evaporator Follow the general procedures given on
page 2.
NOTE:
Location for the insertion of spray
nozzle is indicated by the red arrow
in the illustration.
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AIR CONDITIONING EVAPORATOR ODOR ± AC001±97 September 12, 1997
LS 4003. Reinstallation of parts.
('93±'94)
(Continued) (a) Insert the (2) filters into the cooling
unit as shown in the illustration.
NOTE:
Insert a clean air filter with it's knob
facing downwards, then slide it forward
and install the second filter in the same
manner.
(b) Assemble the rubber insulator on the plate.
CAUTION:
To prevent the cooling unit from leaking
water, pull the three rubber projections
from the other side of the plate to make
sure that the rubber insulator seals
properly against the plate.
(c) Install the plate on the cooling unit and secure with the (2) wing nuts.
CAUTION:
To prevent water leaks, verify that the
cooling unit and plate are fully secure
before tightening the wing nuts.
NOTE:
Before installing the plate on the
cooling unit, coat the rubber insulator
with water for easier assembly.
(d) Reinstall the lamp.
(e) Reassemble the Undercover.
Page 8 of 11
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Page 9 of 11
AIR CONDITIONING EVAPORATOR ODOR ± AC001±97 September 12, 1997
SC 3001. Removal of parts.
SC 400 (a) Remove two clips using the clip
remover then remove the undercover.
NOTE:
Pull down the clip areas (4 places) of
the Undercover to remove.
(b) Remove the (2) wing nuts and the plate on the bottom of the cooling unit.
CAUTION:
The plate and wing nuts will be reused.
(c) Remove the (2) filters from the cooling unit.
2. Clean the Evaporator Follow the general procedures given on
page 2.
NOTE:
Location for the insertion of spray
nozzle is indicated by the red arrow
in the illustration.
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AIR CONDITIONING EVAPORATOR ODOR ± AC001±97 September 12, 1997
SC 3003. Reinstallation of parts.
SC 400
(Continued) (a) Insert the (2) filters into the cooling
unit as shown in the illustration.
NOTE:
Insert a clean air filter with it's knob
facing downwards, then slide it forward
and install the second filter in the same
manner.
(b) Assemble the rubber insulator on the plate.
CAUTION:
To prevent the cooling unit from leaking
water, pull the three rubber projections
from the other side of the plate to make
sure that the rubber insulator seals
properly against the plate.
(c) Install the plate on the cooling unit and secure with the (2) wing nuts.
CAUTION:
To prevent water leaks, verify that the
cooling unit and plate are fully secure
before tightening the wing nuts.
NOTE:
Before installing the plate on the
cooling unit, coat the rubber insulator
with water for easier assembly.
(d) Reassemble the Undercover.
Page 10 of 11
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Page 11 of 11
AIR CONDITIONING EVAPORATOR ODOR ± AC001±97 September 12, 1997
LX 4501. Removal of parts.
(a) Remove the glove compartment door.
(b) Remove the A/C Amplifier.
(c) Remove power transistor.
2. Clean the Evaporator Follow the general procedures given on
page 2.
3. Reinstallation of parts. Reinstall the parts in reverse order
of removal described in step 1.
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Lexus Supports ASE CertificationPage 1 of 12
Title:
SENSOR INSPECTION FOR AIR
CONDITIONING SYSTEM
Models:
'90 ± Current All Models
Technical Service
Information Bulletin
December 16, 2004
AC005-04
This service bulletin contains inspection procedures to more precisely confi\
rm proper
operation of the following temperature sensors of the air conditioning s\
ystem. Follow the
procedures in this service bulletin when inspecting these sensors. These\
contents will be
reflected in future repair manuals.
Room Temperature Sensor
Ambient Temperature Sensor
Air Duct Sensor
Evaporator Temperature Sensor
Solar Sensor
Room Humidity Sensor
All 1990 ± Current model year Lexus vehicles.
OP CODEDESCRIPTIONTIMEOFPT1T2
N/ANot Applicable to Warranty±±±±
HEATING & AIR CONDITIONING
Introduction
Applicable Vehicles
Warranty
Information
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SENSOR INSPECTION FOR AIR CONDITIONING SYSTEM ± AC005-04 December 16, 2004
Page 2 of 12
1. Inspect Room Temperature Sensor.
A. Measure the sensor resistance.
Resistance Value at 77 5F
(25 5C)1700 +/± 85 W
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.
TEMPERATURE 5F ( 5C)SPECIFICATION k W
50 (10)3.00 to 3.73
59 (15)2.45 to 2.88
68 (20)1.95 to 2.30
77 (25)1.60 to 1.80
86 (30)1.28 to 1.47
95 (35)1.00 to 1.22
104 (40)0.80 to 1.00
113 (45)0.65 to 0.85
122 (50)0.50 to 0.70
131 (55)0.44 to 0.60
140 (60)0.36 to 0.50
Inspection
Procedure
Resistance
k W
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0.0
32
(0) 68
(20) 104
(40) 140
(60)
Temperature 5F ( 5C)
Max
Min
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SENSOR INSPECTION FOR AIR CONDITIONING SYSTEM ± AC005-04 December 16, 2004
Page 3 of 12
2. Inspect Ambient
Temperature Sensor.
A. Measure the sensor resistance according to the selected graph
(specification).
Resistance Value at 77 5F
(25 5C)1700 +/± 85 W
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.
TEMPERATURE 5F ( 5C)SPECIFICATION k W
50 (10)3.00 to 3.73
59 (15)2.45 to 2.88
68 (20)1.95 to 2.30
77 (25)1.60 to 1.80
86 (30)1.28 to 1.47
95 (35)1.00 to 1.22
104 (40)0.80 to 1.00
113 (45)0.65 to 0.85
122 (50)0.50 to 0.70
131 (55)0.44 to 0.60
140 (60)0.36 to 0.50
Inspection
Procedure
(Continued)
Resistance
k W
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0.0
32
(0) 68
(20) 104
(40) 140
(60)
Temperature 5F ( 5C)
Max
Min
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SENSOR INSPECTION FOR AIR CONDITIONING SYSTEM ± AC005-04 December 16, 2004
Page 4 of 12
3. Inspect Air Duct Sensor.
A. Measure the sensor resistanceaccording to the table and
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.
TEMPERATURE 5F ( 5C)SPECIFICATION k W
50 (10)9.48 to 10.49
59 (15)7.50 to 8.28
68 (20)5.95 to 6.57
77 (25)4.77 to 5.25
86 (30)3.85 to 4.21
95 (35)3.12 to 3.40
104 (40)2.53 to 2.79
113 (45)2.06 to 2.30
122 (50)1.69 to 1.91
131 (55)1.39 to 1.59
140 (60)1.15 to 1.33
Inspection
Procedure
(Continued)
Resistance
k W
15.0
10.0
5.0
0.0 32
(0) 68
(20) 104
(40) 140
(60)
Temperature 5F ( 5C)
Max
Min 176
(80)
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