1991 LEXUS SC300 heating

Lexus Supports ASE CertificationPage 1 of 4
Title:
R-12 AIR CONDITIONER SYSTEM
RETROFIT
Models:
'90±'93 ES 250/300, SC 400/300, LS 400
Technical Service
Information Bulletin
April 3, 1998
AC001±98
The following information should be used for guidance when retrofitting veh\
icle air
conditioning systems from R±12 to R134a refrigerant.
1990±1992 model year LS 400, 1990±1991 model year ES 250, 1992±1993 model
year ES 300, 1992±1993 model year SC 300, 1992±1993 model year SC 400
All parts required for retrofit are available through the normal parts s\
ystem:
IDENTIFICATIONREQUIRED PARTS & MATERIALS
MODELCOMPRESSORRETROFIT SETRECEIVERND OIL 8CHARGE
LS 40010PA2088471±16050170 cc1000 g
ES 25010PA17V88840±33020 (1)
l
88471±12040100 cc650 g
ES 300plus
90099±14044 (2)SC 30010PA1790099±14044 (2)
90099±14045 (1)88471±16050150 cc900 g
SC400
90099 14045 (1)g
NOTE:
Retrofit Set 88840±33020 includes: 88374±33010 Low pressure side service fitting adaptor (7/16±20 UNF)
88374±33020 High pressure side service fitting adaptor (3/8±20 UNF)
88723±20040 R134a ªUSE ONLYº label (ND Oil 8 for 10P, 10PA compressor)
88723±33050 Retrofit Caution Label
90099±14046 Piping O±rings for discharge hose (quantity 2)
Required for all models (not included in set): 90099±14044 Receiver O±rings (quantity 2)
08885±09107 ND±Oil 8
Also available as needed: 88374±33040 L±shaped low pressure side service fitting adaptor
88374±33050 L±shaped high pressure side service fitting adaptor
OP CODENWCDESCRIPTIONTIMEOPNT1T2
Not Applicable to Warranty
Affected Vehicles page 1 . . . . . . . . . .
Service Precautions page 3 . . . . . . . .
Retrofit Kit Parts page 1 . . . . . . . . . . .
Required Parts page 2 . . . . . . . . . . . . . Required Tools & Materials page 2
. . .
Retrofitting Overview page 2 . . . . . . . . .
Repair Procedures page 3 . . . . . . . . . . .
Warranty Information page 1 . . . . . . . . .
HEATING & AIR CONDITIONING
Introduction
Affected
Vehicles
Parts
Information
Warranty
Information
Table of
Contents
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R±12 AIR CONDITIONER SYSTEM RETROFIT ± AC001±98 April 3, 1998
Page 3 of 4
A. Refrigerant handling
1. Do not handle refrigerant in an enclosed area or near an open flame.
2. Always wear eye protection.
3. Avoid getting liquid refrigerant in your eyes or on your skin.
4. Never heat a container with an open flame.
5. Keep containers below 104 °F.
6. When heating a refrigerant can with water, keep the valve above water.
7. Never reuse empty service cans.
B. Replacing parts 1. Plug off any open connections to prevent the entry of moisture and dust.
2. Do not remove plugs from Receiver ports until it is ready for installati\
on.
C. Tightening connecting parts
1. Apply a few drops of ND±Oil 8 compressor oil to O±ring fittings be\
fore tightening.
2. Avoid twisting refrigerant piping when installing R134a service fitting a\
dapters.
3. Tighten all fittings to specified torque.
D. Recharging with A/C ªonº
1. Never open the high side valve with the engine running.
2. Never run the A/C system when low on refrigerant as compressor damage ma\
yoccur.
3. Never charge the system with liquid refrigerant with the engine running.\
4. Be careful not to overcharge the system.
NOTE:
Oil removed during R±12 evacuation should not be used with an R134a Syst\
em.
A. Vehicle Inspection:
Ensure the integrity of the A/C system before proceeding with retrofit.
B. Recover R±12 using R±12 recovery/recycling/recharging equipment: Follow Lexus recommended procedure.
C. Install R134a service fitting adapters: 1. Remove valve cores from R±12 service fittings and discard.
2. Clean external threads of the R±12 service fittings.
3. Apply adhesive to threads (Loctite 262 or equivalent), screw on R134a \
adapterfittings, and tighten to 13 ft±lb.
NOTE:
Vehicles with more than 2 service fittings will require the installation \
of additional
adaptors. All service fittings must have R134a adaptors installed.
D. Replace piping and hose O±rings:
1. Disconnect discharge hose from compressor.
2. Remove and discard old O±rings.
3. Lubricate with ND±Oil 8 and install new O±rings.
4. Disconnect discharge hose from condenser.
5. Lubricate and install retrofit O±rings with ND±Oil 8.
6. Reconnect hoses and torque to specification. (Specifications can be fou\
nd in applicable manuals/guides.)
Service
Precautions
Repair
Procedure
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wTighten the O±ring fittings or the bolted type fittings to
the specified torque.
Precautions When Charging Refrigerant
1. DO NOT OPERATE COMPRESSOR WITHOUT ENOUGH
REFRIGERANT IN REFRIGERANT CYCLE
If there is not enough refrigerant in the refrigerant cycle, oil
lubrication will be insufficient and compressor burnout may
occur, so take care to avoid this.
2. DO NOT OPEN HIGH PRESSURE VALVE OF MANIFOLD GAUGE WITH COMPRESSOR OPERATING
If the high pressure valve is opened, refrigerant flows in the
reverse direction and could cause the charging cylinder to
rupture, so open and close the low pressure valve only.
3. BE CAREFUL NOT TO OVERCHARGE WITH REFRIGERANT IN SYSTEM
If refrigerant is overcharged, it causes trouble such as insuffi-
cient cooling, poor fuel economy, engine overheating etc.
Electrical Parts
Before removing and inspecting the electrical parts, set the
ignition switch to the LOCK position and disconnect the neg-
ative (±) terminal cable from the battery.
CAUTION: Work must not be started until after at least 20
seconds or longer from the time the negative (±) terminal
cable is disconnected.
SRS Airbag System
Failure to carry out service operations in the correct se-
quence could cause the airbag system to deploy, possibly
leading to a serious accident.
When removal or installation of the parts and the yellow wire
harness and connector for the airbag is necessary, refer to
the precautionary notices in the AB section before perform-
ing the operation.
±
AIR CONDITIONING SYSTEM General DescriptionAC±5
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ASSEMBLY OF FRONT SEAT
(See page BO±63)
ASSEMBLE FRONT SEAT PARTS BY FOLLOWING DIS-
ASSEMBLY SEQUENCE IN REVERSE HINT:
wUsing hog ring pliers, install the new hog ring.
wBefore installing the reclining adjuster, align the
matchmarks.
wIf creases occur in the front seat, stretch out the
creases by heating them with a dryer, etc.
If the creases still cannot be removed, spray them lightly
with a vaporizer before applying the hair dry again.
±
BODY Seat (Front Seat)BO±65
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ASSEMBLY OF REAR SEAT
(See page BO±68)
ASSEMBLE THE REAR SEAT PARTS BY FOLLOWING DIS-
ASSEMBLY SEQUENCE IN REVERSE HINT:
wUsing a hog ring pliers install the new hog ring.
wIf creases occur in the front seat, stretch out the
creases by heating then with a dryer, etc.If the creases still cannot be removed, spray them lightly
with a vaporizer before applying the hair dryer again.
±
BODY Seat (Rear Seat)BO±69
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FRONT DOOR PANEL (CUT)
REMOVAL
Cut and Join
LocationCut and Join Location
Heat Slightly Hemming Location
Disc Sander
1. Cut and join the parts at the location shown above.
2. After grinding off the hemming location, remove the outer panel.
HINT: Slightly heating the outer panel will soften thesealer and make removal easier.
BODY PANEL REPLACEMENTRE-38
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A/C COMPRESSOR OIL APPLICATIONSPage 1 of 1
Care must be taken to use only refrigerant oil which is compatible to the vehicle's system.
Following are A/C oil application charts for both R±12 and HFC±134\
a systems:
R±12 SYSTEMS
MODEL OIL TYPE PART NUMBER QUANTITY
All Models ND±Oil 6 P/N (88899±28040) 60 cc (or Equivalent) P/N (07117±68040) 500 cc
HFC±134A SYSTEMS MODEL OIL TYPE PART NUMBER QUANTITY
All Models ND±Oil 8 P/N (08885±09109) 40 cc P/N (08885±09107) 250 cc
HEATING & AIR CONDITIONING
AC93±004
OCTOBER 22, 1993
ALL MODELS
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DATE:JULY 19, 1996
Title1992 - 1995 SC 300/400 A/C CONTROL ASSEMBLY SERVICE PARTSPage 1 of 6
To allow repairs to the A/C Control Assembly, service parts are now available. The following
information on parts and troubleshooting will aid you in addressing comp\
laints with the LCD
display, night illumination or switch indicators.
PREVIOUSLY AVAILABLE PARTS
:
CURRENTLY AVAILABLE PARTS
:
* Face Plate is not available as a separate part.
REF: HEATING & AIR CONDITIONING
NO:AC004-96
MODEL:SC 300/400
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