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been shown to be combustible at
elevated pressures. These mixtures, if ignited, may cause injury or
property damage. Additional health and safety info rmation may be obtained from refrigerant manu-
facturers.
Oil Precaution INFOID:0000000004307045
• Use only specified oil for the HFC-134a (R-134a) A/C system and HFC-134a (R-134a) components. If oil
other than that specified is used, comp ressor malfunction is likely to occur.
• The specified HFC-134a (R-134a) oil rapidly absorbs mo isture from the atmosphere. The following handling
precautions must be observed:
- When removing refrigerant components from a vehicle, immediately cap (seal) the component to minimize the entry of moisture from the atmosphere.
- When installing refrigerant components to a vehicle, do not remove the caps (unseal) until just before con- necting the components. Connect all refrigerant loop components as quickly as possible to minimize the
entry of moisture into system.
- Only use the specified oil from a sealed container. Imm ediately reseal containers of oil. Without proper seal-
ing, oil will become moisture saturated and should not be used.
• Avoid breathing A/C refrigerant and oil vapor or mist. Exposure may irritate eyes, nose and throat.
Use only approved recovery/recycling equipment to discharge HFC-134a (R-134a) refrigerant. If accidental
system discharge occurs, ventilate work area before re suming service. Additional health and safety informa-
tion may be obtained from refrigerant and oil manufacturers.
• Do not allow A/C oil to come in contact with styrofoam parts. Damage may result.
Precaution for Refrigerant Connection INFOID:0000000004307046
A new type refrigerant connection has been introduced to a ll refrigerant lines except the following location.
• Expansion valve to evaporator
• Refrigerant pressure sensor to condenser
FEATURES OF NEW TYPE REFRIGERANT CONNECTION
• The O-ring has been relocated. It has also been provided with a groove for proper installation. This elimi- nates the chance of the O-ring being caught in, or damaged by, the mating part. The sealing direction of the
O-ring is now set vertically in relation to the contacti ng surface of the mating part to improve sealing charac-
teristics.
• The reaction force of the O-ring will not occur in the dire ction that causes the joint to pull out, thereby facili-
tating piping connections.
O-RING AND REFRIGERANT CONNECTION

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O-Ring Part Numbers and Specifications
CAUTION:
When replacing or cleaning refrigerant cycle components, observe the following.
• When the compressor is removed, store it in the sam e position as it is when installed on the vehicle.
Doing so will cause oil to en ter the low-pressure chamber.
• When connecting tubes, always use a to rque wrench and a back-up wrench.
• After disconnecting tubes, immediately plug all op enings to prevent entry of dirt and moisture.
• When installing an air conditione r in the vehicle, connect the pipes as the final stage of the opera-
tion. Do not remove the seal caps of pipes and other components until just before required for con-
nection.
• Allow components stored in cool areas to warm to working area temperature before removing seal
caps. This prevents condensation from forming inside A/C components.
• Thoroughly remove moisture from the refriger ation system before charging the refrigerant.
• Always replace used O-rings.
• When connecting tube, apply the speci fied A/C oil to circle of the O-rings. Be careful not to apply oil
to threaded portion. Refer to MTC-90, " Oil " .
• O-ring must be closely attached to dented portion of tube.
• When replacing the O-ring, be careful not to damage O-ring and tube.
• Connect tube until you hear it cl ick, then tighten the nut or bolt by hand until snug. Make sure that
the O-ring is installed to tube correctly.
• After connecting line, perform leak test and make sure that there is no leakage from connections.
When the refrigerant leaking point is found, disconnect that line and replace the O-ring. Then tighten
connections of seal seat to the specified torque.
Precaution for Service of Compressor INFOID:0000000004307047
• Plug all openings to prevent moisture and foreign matter from entering.
Connection type Piping connection point Part number QTY O-ring size
New Condenser to high-pressure flexible hose 92472 N8210 1 12
Condenser to high-pressure pipe 92471 N8210 1 8
Low-pressure flexible hose to expansion valve 92473 N8210 1 16
High-pressure pipe to expansion valve 92471 N8210 1 8
Compressor to low-pressure flexible hose 92474 N8210 1 19
Compressor to high-pressure flexible hose 92472 N8210 1 12
Liquid tank to condenser pipe Inlet
92471 N8210 1
8
Outlet 1
Former Refrigerant pressure sensor to condenser J2476 89956 1 10
Expansion valve to evaporator Inlet 92471 N8200 2 12
Outlet 92473 N8200 2 16

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REFRIGERATION SYSTEM
Refrigerant Cycle INFOID:0000000004307053
REFRIGERANT FLOW The refrigerant flows in the standard pattern, that is , through the compressor, the condenser with liquid tank,
through the evaporator, and back to the compressor. T he refrigerant evaporation through the evaporator is
controlled by an externally equalized expansion valve, located inside the evaporator case.
FREEZE PROTECTION Under usual operating conditions, when the A/C is s witched ON, the compressor runs continuously, and the
evaporator pressure, and temperature is controlled by the compressor to prevent freeze up.
Refrigerant System Protection INFOID:0000000004307054
REFRIGERANT PRESSURE SENSOR The refrigerant system is protected against excessively hi gh or low pressures by the refrigerant pressure sen-
sor, located on the condenser. If the system pressure rise s above, or falls below the specifications, the refrig-
erant pressure sensor detects the pressure inside t he refrigerant line and sends the voltage signal to the ECM.
ECM makes the A/C relay go OFF and stops the compressor when pressure on the high-pressure side
detected by refrigerant pressure sensor is over about 2,746 kPa (27.46 bar, 28.0 kg/cm 2
, 398 psi), or below
about 134 kPa (1.34 bar, 1.4 kg/cm 2
, 20 psi).
PRESSURE RELIEF VALVE The refrigerant system is also protected by a pressure relief valve, located in the rear head of the compressor.
When the pressure of refrigerant in the system in creases to an unusual level [more than 3.8 MPa (38 bar,
38.76 kg/cm 2
, 551 psi)], the release port on the pressure relief valve automatically opens and releases refrig-
erant into the atmosphere.

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Both High- and Low-pressure Sides are Too Low
Low-pressure Side Some times Becomes Negative
Low-pressure Side Becomes Negative Gauge indication Refrigerant cycle Probable cause Corrective action
Both high- and low-pressure
sides are too low. • There is a big temperature dif-
ference between liquid tank
outlet and inlet. Outlet tem-
perature is extremely low.
• Liquid tank inlet and expan- sion valve are frosted. Liquid tank inside is slightly
clogged. • Replace liquid tank.
• Check oil for contamination.
• Temperature of expansion valve inlet is extremely low as
compared with areas near liq-
uid tank.
• Expansion valve inlet may be
frosted.
• Temperature difference oc- curs somewhere in high-pres-
sure side. High-pressure pipe located be-
tween liquid tank and expansion
valve is clogged. • Check and repair malfunc-
tioning parts.
• Check oil for contamination.
Expansion valve and liquid tank
are warm or only cool when
touched. Low refrigerant charge.
↓
Leaking fittings or components Check refrigerant for leaks.
Refer to MTC-86, " Checking of
Refrigerant Leaks " .
There is a big temperature dif-
ference between expansion
valve inlet and outlet while the
valve itself is frosted. Expansion valve closes a little
compared with the specification.
↓
1. Improper expansion valve
adjustment.
2. Malfunctioning expansion valve.
3. Outlet and inlet may be clogged. • Remove foreign particles by
using compressed air.
• Replace expansion valve.
• Check oil for contamination.
An area of the low-pressure pipe
is colder than areas near the
evaporator outlet. Low-pressure pipe is clogged or
crushed. • Check and repair malfunc-
tioning parts.
• Check oil for contamination.
Air flow volume is not enough or
is too low. Evaporator is frozen.• Check thermo control amp.
Refer to MTC-37, " Magnet
Clutch Circuit (If Equipped) "
.
• Replace compressor.
• Repair evaporator fins.
• Replace evaporator.
• Refer to MTC-33, " Front
Blower Motor Circuit " .

Operational Check " *2.
EM-14, " Checking " (HR16DE) or
EM- 136, " Checking Drive Belts "
(MR18DE) *3.
MTC-45, " Insufficient Cooling "
*4.
MTC-86, " Removal and Installation of
Expansion Valve " *5.
MTC-78, " Removal and Installation of
Compressor - HR16DE " or
MTC-80, " Removal and Installation of Com-
pressor - MR18DE " *6
MTC-78, " Removal and Installation of
Compressor - HR16DE " or
MTC-80, " Removal and Installation of Com-
pressor - MR18DE "
*7.
MTC-78, " Removal and Installation of
Compressor - HR16DE " or
MTC-80, " Removal and Installation of Com-
pressor - MR18DE " *8.
MTC-17, " Maintenance of Oil Quanti-
ty in Compressor " *9
MTC-84, " Removal and Installation of
Liquid Tank "

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40. Expansion valve grommet 41. O-ring 42. Evaporator
43. Cooler pipe assembly

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4. Remove liquid tank bracket (1
) from protruding part of con-
denser (2).
5. Slide liquid tank (3) upward, and then remove liquid tank (3).
INSTALLATION Installation is in the reverse order of removal.
CAUTION:
• Make sure liquid tank bracket (2) is securely installed at pro-
trusion of condenser (3). [Make sure liquid tank bracket (2)
does not move to a position belo w center of liquid tank (1).]
• Replace O-rings for A/C piping with new ones, and apply com-
pressor oil when installing.
• When recharging refrigerant, check for leaks. Refer to MTC-86, " Checking of Refrigerant Leaks " .
Removal and Installation of Evaporator INFOID:0000000004307098
REMOVAL 1. Remove A/C unit assembly. Refer to MTC-58, " Removal and Installation " .
CAUTION:
Cap or wrap the joint of the pipe with suitable ma terial such as vinyl tape to avoid the entry of air.
2. Remove air conditioner filter. Refer to MTC-68, " Removal and Installation " .
3. Remove foot duct (right). Refer to MTC-69, " Removal and Installation " .
4. Remove screws (A), and then remove expansion valve cover (1).
5. Remove screws (A), and then remove evaporator cover (1). RJIA3879J

Removal and Installation " .
3. Remove lower dash insulator.
4. Disconnect low-pressure flexible hose and high-pressure pipe from evaporator. Refer to MTC-58," Removal and Installation " .
5. Remove expansion valve bolts (A), and then remove expansion valve (1).
CAUTION:
Cap or wrap the joint of the pi pe with suitable material such
as vinyl tape to avoid the entry of air.
INSTALLATION
Installation is in the reverse order of removal.
CAUTION:
• Replace O-rings of evaporator with new ones, and apply compressor oil when installing.
• When recharging refrigerant, check for leaks.
Checking of Refrigerant Leaks INFOID:0000000004307100
Perform a visual inspection of all refrigeration parts, fittings, hoses and components for signs of A/C oil leak-
age, damage and corrosion. A/C oil leakage may indicate an area of refrigerant leakage. Allow extra inspec-
tion time in these areas when using either an electroni c refrigerant leak detector or fluorescent dye leak
detector.
If dye is observed, confirm the leak with an electronic refrigerant leak detector. It is possible a prior leak was
repaired and not properly cleaned.
When searching for leaks, do not stop when one leak is found but continue to check for additional leaks at all
system components and connections.
When searching for refrigerant leaks using an electroni c leak detector, move the probe along the suspected
leak area at 25 to 50 mm (1 to 2 in) per sec ond and no further than 1/4 inch from the component.
CAUTION: