ect LEXUS SC300 1991 Service Repair Manual

AIR CONDITIONING EVAPORATOR ODOR ± AC001±97 September 12, 1997
General1. Preparation of freshener solution:
Procedure (a) Invert freshener container and shake vigorously for 30 seconds.
(b) Mix 3.4 fl. oz. of freshener (1 container) with 30 fl. oz. to make 1 q\
t. of solution.
2. Drying the evaporator: Dry the evaporator for 10 minutes with the following settings:
A/C: Off
. . . . . . . . . . .
Air Outlet: Foot
. . . . . .
Mode: Recirc.
. . . . . . . . . .
Blower: High
. . . . . . . .
Te m p : Max Warm
. . . . . . . . . .
3. Evaporator Treatment Preparation: (a) Ensure availability of 30±45 psi compressed air to be used with spray\
gun for application of freshener.
(b) Place a tray under the evaporator housing drain hose to collect used cle\
aning solution.
(c) Place shop cloth under the evaporator housing in the vehicle to prevent \
cleaning solution from dripping onto the floor mat.
4. Vehicle Preparation: See specific model section.
5. Evaporator treatment: (a) Set HVAC mode as follows: A/C: Off
. . . . . . . . . . .
Air Outlet: Face
. . . . . .
Mode: Fresh
. . . . . . . . . .
Blower: High
. . . . . . . .
Te m p : Max Warm
. . . . . . . . . .
Windows: Open
. . . . . .
(b) Insert spray nozzle into the filter inlet and spray the entire quantity (1 qt.) of
freshener solution into the evaporator
while moving the nozzle around to
cover the complete evaporator surface.
(c) Turn the blower OFF.
6. Reinstallation of Parts.
7. Completion of Treatment. (a) Dry the evaporator for 30 minutes with the following settings:
A/C: Off
. . . . . . . . . . .
Air Outlet: Foot
. . . . . .
Mode: Recirc.
. . . . . . . . . .
Blower: High
. . . . . . . .
Te m p : Max Warm
. . . . . . . . . .
Windows: Closed
. . . . . .
(b) If the vehicle still has alcohol smell, open windows for ventilation. Do not turn on
the AC switch until the evaporator is
completely dry as this can reduce the
effectiveness of the solution.
Page 2 of 11
CAUTION
Do not get into the vehicle during
this drying operation.
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Page 3 of 11
AIR CONDITIONING EVAPORATOR ODOR ± AC001±97 September 12, 1997
ES 3001. Removal of parts.
('92±'96) (a) Pull down the carpet from the center
console as indicated by red arrow in the
illustration.
(b) Remove the plate on the side of the heater unit using steps and
,
indicated with red arrows to show
direction, in the illustration.
CAUTION:
Do not bend the cable.
NOTE:
The Plate will be reused.
(c) Remove the filter.
(d) Remove the blower controller.
2. Clean the Evaporator. Follow the general procedures given
on page 2.
NOTE:
Location for insertion of spray nozzle
is indicated by the red arrow in the
illustration.
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AIR CONDITIONING EVAPORATOR ± AC001±97 September 12, 1997
ES 3003. Reinstallation of parts.
('92±'96)
(Continued) (a) Insert the filter (up side) into the
heater unit following the numbered
steps shown in the illustration.
(b) Insert the filter (down side) into the heater unit.
(c) Reinstall the plate on the side of the heater unit using steps and
,
indicated with red arrows to show
direction, in the illustration.
CAUTION:
Confirm that the plate is secure.
(d) Restore the carpet to its original position taking care not to bend
the cable.
Page 4 of 11
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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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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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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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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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