Conditioning SUBARU LEGACY 1996 Service User Guide

1. Safety Precautions
1. HFC-134a AIR CONDITIONING SYSTEM
Component parts of the cooling system, refrigerant, com-
pressor oil, and other parts are not the same for the HFC-
134a system and the older CFC-12 system. Do not inter-
change parts or liquid.
Vehicles with HFC-134a air conditioning systems, use only
HFC-134a parts that are indicated on a label attached to
the vehicle. Before performing any maintenance, verify the
type of air conditioning system installed in the vehicle.
B4M0780
2. COMPRESSOR OIL
Do not use any compressor oil that is not specifically des-
ignated for the HFC-134a air conditioning system; only use
ZXL200PG. Also, do not use HFC-134a compressor oil in
the CFC-12 air conditioning system. If compression oils are
mixed, poor lubrication will result and the compressor itself
may be damaged.
Because HFC-134a compressor oil is very hygroscopic
(easily absorbs moisture), when parts of the air condition-
ing system are being removed, quickly install a blind plug
to prevent contact with the outside air. Also, always make
sure that the service container for compressor oil is tightly
closed except when in use. Store compressor oil in a tightly
closed steel container.
9
4-7SERVICE PROCEDURE
1. Safety Precautions

3. REFRIGERANT
Do not put CFC-12 refrigerant into a HFC-134a air condi-
tioning system. Also, do not put HFC-134a refrigerant into
a CFC-12 air conditioning system. If the wrong refrigerant
is used, poor lubrication will result and the compressor
itself may be destroyed.
G4M0979
4. HANDLING OF REFRIGERANT
Because refrigerant boils at approx. 30°C (22°F) at sea
level, it is cold enough to give you severe frostbite. Always
wear goggles to protect your eyes and gloves to protect
your hands. Also, even under the pressures normally found
in CFC-12 containers, refrigerant will boil with the addition
of heat. This could raise the pressure inside the container
to a dangerous level.
Never expose a can of HFC-134a to direct sunlight, or to
temperatures over 40°C (104°F). One more thing to
remember about HFC-134a is that when it is exposed to an
open flame or to hot metal, it forms phosgene, a deadly
gas. Do not discharge HFC-134a into the atmosphere on
purpose. Always read and follow the precautions on the
HFC-134a bottle.
10
4-7SERVICE PROCEDURE
1. Safety Precautions

1. Air Conditioning System Diagnosis
41
4-7DIAGNOSTICS
1. Air Conditioning System Diagnosis

2. Performance Test Diagnosis
If various conditions caused to other air conditioning
system, the characteristics revealed on manifold gauge
reading are shown in the following:
As to the method of a performance test, refer to the item
of“Performance Test”.
Each shaded area on the following tables indicates a read-
ing of the normal system when the temperature of outside
air is 32.5°C (91°F).
Condition Probable cause Corrective action
INSUFFICIENT REFRIGERANT CHARGE
G4M0673
Insufficient cooling Refrigerant is small, or
leaking a little.1. Perform leak test.
2. Repair leak.
3. Charge system.
Evacuate, as
necessary, and
recharge system.
ALMOST NO REFRIGERANT
G4M0674
No cooling action Serious refrigerant leak.Stop compressor
immediately.
1. Perform leak test.
2. Discharge system.
3. Repair leak(s).
4. Replace receiver
drier if necessary.
5. Check oil level.
6. Evacuate and
recharge system.
FAULTY EXPANSION VALVE
G4M0675
Slight cooling;
Sweating or frosted
expansion valve inlet.Expansion valve
restricts refrigerant flow.
Expansion valve is
clogged.
Expansion valve is
inoperative.
Valve stuck closed.
Thermal bulb has lost
charge.If valve inlet reveals
sweat or frost:
1. Discharge system.
2. Remove valve and
clean it. Replace it if
necessary.
3. Evacuate system.
4. Charge system.
If valve does not oper-
ate:
1. Discharge system.
2. Replace valve.
3. Evacuate and charge
system.
42
4-7DIAGNOSTICS
2. Performance Test Diagnosis

ABBREVIATION LIST
Abbr. Full name
A.B.S. Antilock Brake System
ACC Accessory
A/C Air Conditioning
AD Auto Down
AT Automatic Transmission
AU Auto Up
+B Battery
DN Down
DRL Daytime Running Light
E Ground
F/B Fuse & Joint Box
FL1.5 Fusible link 1.5 mm
2
IG Ignition
Illumi. Illumination
Abbr. Full name
LH Left Hand
Lo Low
M Motor
M/B Main Fuse Box
MG Magnet
Mi Middle
OP Optional Parts
PASS Passing
RH Right Hand
SBF Slow Blow Fuse
S.M.J. Super Multiple Junction
ST Starter
SW Switch
T.C.S. Traction Control System
UP Up
WASH Washer
17
6-3WIRING DIAGRAM
5. How to Use Super Multiple Junction (S.M.J.)

3. AIR CONDITIONING SYSTEM

LHD model
31
6-3WIRING DIAGRAM
6. Wiring Diagram

3. AIR CONDITIONING SYSTEM

RHD model
BUR45-02
32
6-3WIRING DIAGRAM
6. Wiring Diagram