TOYOTA SUPRA 1995 Service Repair Manual

AIR CONDITIONING SYSTEM
AC±1

GENERAL DESCRIPTION
NEW AIR CONDITIONING SYSTEM WITH
HFC134a
Refrigerant CFC 12 (R 12), previously used in automobiles'
air conditioning systems is believed to contribute towards the
depletion the earth's ozone layer. The ozone layer help to
protect us against the harmful ultraviolet rays of the sun.
A newly developed refrigerant, HFC 134a (R 134 a), does not
the destroy the ozone layer.
PRECAUTIONS FOR SERVICING
HFC134a AIR CONDITIONINGS
1. USE OF NEW REFRIGERANT HFC134a
The very different characteristics of refrigerants HFC134a
and CFC12 have determined the design of their respective
air conditioning systems. Under no circumstances allow
CFC12 to enter an HFC134a system, or vice versa, because
serious damage could occur.
2. USE OF PROPER COMPRESSOR OIL
Compressor oil used in conventional CFC12 air conditioning
systems cannot be used in HFC134a air conditioning sys-
tems.
Always use genuine Toyota R134a air conditioning oil ND±
OIL 8, made expressly for use with HFC134a.
NOTICE: Compressor oil (ND±OIL 8) for HFC134a use ad-
versely affects acrylic resin, so take care not to spill or
spray any compressor oil.
If even a small amount of the wrong oil is changed, it will result
in clouding of the refrigerant.
A large amount will cause the compressor to seize up. AC±2
± AIR CONDITIONING SYSTEMGENERAL DESCRIPTION

3. USE OF PROPER O±RINGS AND SEALS
O±rings and seals used for conventional CFC12 air condi-
tioning systems cannot be used for HFC134a air conditioning
systems.
Always use genuine Toyota HFC134a system O±rings and
seals for HFC134a air conditioning systems.
If O±rings and/or seals for CFC12 air conditioning systems
are used by mistake in the connections of an HFC134a air
conditioning system, the O±ring and seals will foam and swell
resulting in leakage of refrigerant.
4. TIGHTEN CONNECTING PARTS SECURELY
Securely tighten the connecting parts to prevent leaking of
refrigerant gas.
wApply a few drops of compressor oil to O±ring fittings for
easy tightening and to prevent leaking of refrigerant
gas.
CAUTION: Apply only ND±OIL 8 compressor oil.
wTighten the nuts using 2 wrenches to avoid twisting the
tube.
wTighten the O±ring fittings or the bolted type fittings to
the specified torque.
5. INSERT PLUG IMMEDIATELY IN DISCONNECTED PARTS
Insert a plug immediately in the disconnected parts to pre-
vent the ingress of moisture and dust.
6. DO NOT REMOVE PLUG FROM NEW PARTS UNTIL
IMMEDIATELY BEFORE INSTALLATION
7. DISCHARGE GAS IN NEW COMPRESSOR FROM
CHARGING VALVE BEFORE INSTALLING IT
If the gas in the new compressor is not discharged first, com-
pressor oil will spray out with gas when the plug is removed.
± AIR CONDITIONING SYSTEMGENERAL DESCRIPTIONAC±3

SERVICE TOOLS FOR HFC134a AIR
CONDITIONING
When servicing HFC134a air conditioning systems always
use the HFC134a dedicated manifold gauges, gas leak de-
tector and vacuum pump adaptor.
1. USE MANIFOLD GAUGES FOR HFC134a AIR
CONDITIONING
Always use HFC134a dedicated manifold gauges to prevent
CFC 12 and CFC 12 compressor oil contaminating the
HFC134a system.
2. USE HFC134a GAS LEAK DETECTOR
Similarly, always use an HFC134a dedicated leak detector.
The CFC12 leak detector is not sufficiently sensitive.
3. USE VACUUM PUMP ADAPTER
By connecting a vacuum pump adapter, the vacuum pump
can be used for both HFC134a and CFC12 air conditioning
systems.
The vacuum pump adaptor has an internal magnetic valve.
When evacuation is completed and the vacuum pump switch
is turned off, the magnetic valve opens allowing the introduc-
tion atmospheric air into the manifold gauges to prevent the
back flow of oil from the vacuum pump into the gauge hose.
CAUTION:
Be sure to turn off the manifold gauge valve immediately
after evacuating the system. Then you may switch off the
vacuum pump. If this order is reversed, the line will be
temporarily open to atmosphere. AC±4
± AIR CONDITIONING SYSTEMGENERAL DESCRIPTION

HANDLING PRECAUTIONS FOR
REFRIGERANT
1. DO NOT HANDLE REFRIGERANT IN AN ENCLOSED
AREA OR NEAR AN OPEN FLAME
2. ALWAYS WEAR EYE PROTECTION
3. BE CAREFUL THAT LIQUID REFRIGERANT DOES NOT
GET IN YOUR EYES OR ON YOUR SKIN
If liquid refrigerant gets in your eyes or on your skin:
(a) Wash the area with lots of cool water.
CAUTION: Do not rub your eyes or skin.
(b) Apply clean petroleum jelly to the skin.
(c) Go immediately to a physician or hospital for professional
treatment.
HANDLING PRECAUTIONS FOR
REFRIGERANT CONTAINER
1. NEVER HEAT CONTAINER OR EXPOSE IT TO NAKED
FLAME
2. BE CAREFUL NOT TO DROP CONTAINER AND NOT TO
APPLY PHYSICAL SHOCKS TO IT
CHARGING AND LEAK±CHECK
METHODS
Evacuate the refrigeration system according to the following
procedures.
Start
EvacuationStop
EvacuationAirtight
CheckRefrigerant
ChargeRefrigerant
ChargeGas Leak
Check
Check and correct
pipe jointsFill refrigerant in gas state until
gauge pressure reads 1 kg/cm2Abnormal indication of
manifold gauges
10 min.Leave for 5 min.
± AIR CONDITIONING SYSTEMGENERAL DESCRIPTIONAC±5

CAUTION:
wBe sure to connect both the high and low pressure
quick±connectors onto the A/C system when evacuating.
If only one side is connected, the system would be open
to atmosphere through the other connector, making it
impossible to maintain vacuum.
wBe sure to turn off the manifold gauge valve immediately
after evacuating the system. Then you may switch off the
vacuum pump.
PRECAUTIONS WHEN CHARGING
REFRIGERANT
1. DO NOT OPERATE COMPRESSOR WITHOUT ENOUGH
REFRIGERANT IN REFRIGERANT SYSTEM
If there is not enough refrigerant in the refrigerant system, oil
lubrication will be insufficient and compressor burnout may
occur, so take care to avoid this.
2. DO NOT OPEN HIGH PRESSURE MANIFOLD VALVE
WHILST COMPRESSOR IS 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 SYSTEM WITH
REFRIGERANT
If refrigerant is overcharged, it causes problems such as in-
sufficient cooling, poor fuel economy, engine overheating
etc.
SUPPLEMENTAL RESTRAINT SYSTEM
(SRS)
Failure to carry out service operations in the correct se-
quence could cause the supplemental restraint system to
deploy, possibly leading to a serious accident.
During 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 RS section before carrying
out operation. AC±6
± AIR CONDITIONING SYSTEMGENERAL DESCRIPTION

DESCRIPTION
PARTS LOCATION
± AIR CONDITIONING SYSTEMDESCRIPTIONAC±7

DAMPERS OPERATION
ModeMode Control
Damper PositionVentHeatDef.
Face
Bi±Level
Foot* I
Foot* II
Foot/Def.
Def.
The size of the circleindicates the proportion of air flow volume.
Foot I indicates the status during automatic control and Foot II indicates the status during manual
control.
AC±8± AIR CONDITIONING SYSTEMDESCRIPTION

PREPARATION
SST (SPECIAL SERVICE TOOLS)
Air Conditioner Service Tool Set
Refrigerant Drain Service Valve
T±Joint
Quick Coupler
Quick Coupler
Refrigerant Charging Gauge
Refrigerant Charging Hose
Refrigerant Charging Hose
Refrigerant Charging Hose
Magnetic Clutch Remover
Magnetic Clutch Stopper
Snap Ring Pliers
Gas Leak Detector Assembly
Discharge (diam. 16 mm)
Suction (diam. 16 mm)
Suction (Blue)
Discharge (Red)
Utility (Green)
± AIR CONDITIONING SYSTEMPREPARATIONAC±9

RECOMMENDED TOOLS
TOYOTA Electrical Tester Set
LUBRICANT 
 Item
 
 Capacity
 
 Classification
 Compressor oil ± ND±OIL 8 or equivalent
  When replacing receiver 10 cc (0.34 fl.oz.) 
  When replacing condenser 40 cc (1.4 fl.oz.) 
  When replacing evaporator 40 cc (1.4 fl.oz.) 
  When replacing compressor 140 cc (4.8 fl.oz.) 
AC±10± AIR CONDITIONING SYSTEMPREPARATION