Nissan Murano Z50 (2003 year). Manual — part 3

PRECAUTIONS

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O-RING AND REFRIGERANT CONNECTION

CAUTION:

The new and former refrigerant connections use different O-ring configurations. Do not confuse O-
rings since they are not interchangeable. If a wrong O-ring is installed, refrigerant will leak at, or
around, the connection.

O-Ring Part Numbers and Specifications

RJIA1744E

Connection type

Piping connection point

Part number

QTY

O-ring size

New

Low-pressure pipe 1 to low-pressure pipe 2 (One-touch joint)

92473 N8221

2

16

Low-pressure pipe 2 to expansion valve

92473 N8210

1

16

High-pressure pipe 1 to high-pressure pipe 2 (One-touch joint)

92471 N8221

2

8

High-pressure pipe 2 to expansion valve

92471 N8210

1

8

Condenser to high-pressure flexible hose

92472 N8210

1

12

Condenser to high-pressure pipe 1

92471 N8210

1

8

Low-pressure flexible hose to low-pressure pipe 1

92474 N8210

1

19

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

92475 71L00

1

12

Outlet

92475 72L00

1

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ATC-12

PRECAUTIONS

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2003 Murano

WARNING:

Make sure all refrigerant is discharged into the recycling equipment and the pressure in the system is
less than atmospheric pressure. Then gradually loosen the discharge side hose fitting and remove it.

CAUTION:

When replacing or cleaning refrigerant cycle components, observe the following.

●

When the compressor is removed, store it in the same position as it is when mounted on the car.
Malfunction to do so will cause lubricant to enter the low-pressure chamber.

●

When connecting tubes, always use a torque wrench and a back-up wrench.

●

After disconnecting tubes, immediately plug all openings to prevent entry of dirt and moisture.

●

When installing an air conditioner 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
connection.

●

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 refrigeration system before charging the refrigerant.

●

Always replace used O-rings.

●

When connecting tube, apply lubricant to circle of the O-rings shown in illustration. Be careful not
to apply lubricant to threaded portion.
Lubricant name: Nissan A/C System Oil Type S
Part number: KLH00-PAGS0

●

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 click, 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 gas leaking point is found, disconnect that line and replace the O-ring. Then tighten con-
nections of seal seat to the specified torque.

RHA861F

PRECAUTIONS

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Precautions for Servicing Compressor

AJS000YC

●

Plug all openings to prevent moisture and foreign matter from entering.

●

When the compressor is removed, store it in the same position as it is when mounted on the car.

●

When replacing or repairing compressor, follow “Maintenance of Lubricant Quantity in Compres-
sor” exactly. Refer to

ATC-22, "Maintenance of Lubricant Quantity in Compressor"

.

●

Keep friction surfaces between clutch and pulley clean. If the surface is contaminated, with lubri-
cant, wipe it off by using a clean waste cloth moistened with thinner.

●

After compressor service operation, turn the compressor shaft by hand more than five turns in
both directions. This will equally distribute lubricant inside the compressor. After the compressor
is installed, let the engine idle and operate the compressor for one hour.

●

After replacing the compressor magnet clutch, apply voltage to the new one and check for usual
operation.

Precautions for Service Equipment

AJS000YD

RECOVERY/RECYCLING EQUIPMENT

Be certain to follow the manufacturers instructions for machine operation and machine maintenance. Never
introduce any refrigerant other than that specified into the machine.

ELECTRONIC LEAK DETECTOR

Be certain to follow the manufacturer

′

s instructions for tester operation and tester maintenance.

VACUUM PUMP

The lubricant contained inside the vacuum pump is not compatible
with the specified lubricant for HFC-134a (R-134a) A/C systems.
The vent side of the vacuum pump is exposed to atmospheric pres-
sure. So the vacuum pump lubricant may migrate out of the pump
into the service hose. This is possible when the pump is switched off
after evacuation (vacuuming) and hose is connected to it.
To prevent this migration, use a manual valve placed near the hose-
to-pump connection, as follows.

●

Usually vacuum pumps have a manual isolator valve as part of
the pump. Close this valve to isolate the service hose from the
pump.

●

For pumps without an isolator, use a hose equipped with a man-
ual shut-off valve near the pump end. Close the valve to isolate
the hose from the pump.

●

If the hose has an automatic shut-off valve, disconnect the hose
from the pump. As long as the hose is connected, the valve is
open and lubricating oil may migrate.

Some one-way valves open when vacuum is applied and close
under a no vacuum condition. Such valves may restrict the pump

′

s

ability to pull a deep vacuum and are not recommended.

MANIFOLD GAUGE SET

Be certain that the gauge face indicates HFC-134a (R-134a or
134a). Be sure the gauge set has 1/2

″

-16 ACME threaded connec-

tions for service hoses. Confirm the set has been used only with
refrigerant HFC-134a (R-134a) and specified lubricants.

RHA270DA

SHA533D

ATC-14

PRECAUTIONS

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SERVICE HOSES

Be certain that the service hoses display the markings described
(colored hose with black stripe). All hoses must include positive shut
-off devices (either manual or automatic) near the end of the hoses
opposite the manifold gauge.

SERVICE COUPLERS

Never attempt to connect HFC-134a (R-134a) service couplers to an
CFC-12 (R-12) A/C system. The HFC-134a (R-134a) couplers will
not properly connect to the CFC-12 (R-12) system. However, if an
improper connection is attempted, discharging and contamination
may occur.

REFRIGERANT WEIGHT SCALE

Verify that no refrigerant other than HFC-134a (R-134a) and speci-
fied lubricants have been used with the scale. If the scale controls
refrigerant flow electronically, the hose fitting must be 1/2

″

-16

ACME.

CALIBRATING ACR4 WEIGHT SCALE

Calibrate the scale every three months.
To calibrate the weight scale on the ACR4 (J-39500-INF):

1.

Press Shift/Reset and Enter at the same time.

2.

Press 8787 . “A1 ” will be displayed.

3.

Remove all weight from the scale.

4.

Press 0 , then press Enter . “0.00 ” will be displayed and change to “A2 ”.

5.

Place a known weight (dumbbell or similar weight), between 4.5 and 8.6 kg (10 and 19 lb.) on the center
of the weight scale.

6.

Enter the known weight using four digits. (Example 10 lb. = 10.00, 10.5 lb. = 10.50)

7.

Press Enter — the display returns to the vacuum mode.

8.

Press Shift/Reset and Enter at the same time.

9.

Press 6 — the known weight on the scale is displayed.

10. Remove the known weight from the scale. “0.00 ” will be displayed.

11. Press Shift/Reset to return the ACR4 to the program mode.

RHA272D

Shut-off valve rotation

A/C service valve

Clockwise

Open

Counterclockwise

Close

RHA273D

RHA274D

PRECAUTIONS

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CHARGING CYLINDER

Using a charging cylinder is not recommended. Refrigerant may be vented into air from cylinder

′

s top valve

when filling the cylinder with refrigerant. Also, the accuracy of the cylinder is generally less than that of an
electronic scale or of quality recycle/recharge equipment.

Precautions for Leak Detection Dye

AJS000YE

●

The A/C system contains a fluorescent leak detection dye used for locating refrigerant leaks. An ultraviolet
(UV) lamp is required to illuminate the dye when inspecting for leaks.

●

Always wear fluorescence enhancing UV safety goggles to protect your eyes and enhance the visibility of
the fluorescent dye.

●

The fluorescent dye leak detector is not a replacement for an electronic refrigerant leak detector. The fluo-
rescent dye leak detector should be used in conjunction with an electronic refrigerant leak detector to (J-
41995) pin-point refrigerant leaks.

●

For your safety and your customer

′

s satisfaction, read and follow all manufacture

′

s operating instructions

and precautions prior to performing the work.

●

A compressor shaft seal should not be repaired because of dye seepage. The compressor shaft seal
should only be repaired after confirming the leak with an electronic refrigerant leak detector (J-41995).

●

Always remove any remaining dye from the leak area after repairs are complete to avoid a misdiagnosis
during a future service.

●

Do not allow dye to come into contact with painted body panels or interior components. If dye is spilled,
clean immediately with the approved dye cleaner. Fluorescent dye left on a surface for an extended period
of time cannot be removed.

●

Do not spray the fluorescent dye cleaning agent on hot surfaces (engine exhaust manifold, etc.).

●

Do not use more than one refrigerant dye bottle (1/4 ounce /7.4 cc) per A/C system.

●

Leak detection dyes for HFC-134a (R-134a) and CFC-12 (R-12) A/C systems are different. Do not use
HFC-134a (R-134a) leak detection dye in CFC-12 (R-12) A/C system or CFC-12 (R-12) leak detector dye
in HFC-134a (R-134a) A/C systems or A/C system damage may result.

●

The fluorescent properties of the dye will remain for over three (3) years unless a compressor malfunction
occurs.

IDENTIFICATION

NOTE:
Vehicles with factory installed fluorescent dye have a green label.
Vehicles without factory installed fluorescent dye have a blue label.

IDENTIFICATION LABEL FOR VEHICLE

Vehicles with factory installed fluorescent dye have this identification
label on the front side of hood.

Wiring Diagrams and Trouble Diagnosis

AJS000YF

When you read wiring diagrams, refer to the following:

●

GI-14, "How to Read Wiring Diagrams"

in GI section.

●

PG-4, "Wiring Diagram - POWER -"

in PG section.

When you perform trouble diagnosis, refer to the following:

●

GI-10, "How to Follow Trouble Diagnoses"

in GI section.

●

GI-26, "How to Perform Efficient Diagnosis for an Electrical Incident"

in GI section.

SHA436FA

ATC-16

PREPARATION

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PREPARATION

PFP:00002

Special Service Tools

AJS000YG

The actual shapes of Kent-Moore tools may differ from those of special service tools illustrated here.

HFC-134a (R-134a) Service Tools and Equipment

AJS000YH

Never mix HFC-134a (R-134a) refrigerant and/or its specified lubricant with CFC-12 (R-12) refrigerant and/or
its lubricant.
Separate and non-interchangeable service equipment must be used for handling each type of refrigerant/lubri-
cant.
Refrigerant container fittings, service hose fittings and service equipment fittings (equipment which handles
refrigerant and/or lubricant) are different between CFC-12 (R-12) and HFC-134a (R-134a). This is to avoid
mixed use of the refrigerants/lubricant.
Adapters that convert one size fitting to another must never be used: refrigerant/lubricant contamination will
occur and compressor malfunction will result.

Tool number
(Kent-Moore No.)
Tool name

Description

(J-44614)
Clutch disc wrench

Removing shaft nut and clutch disc

KV99233130
(J-29884)
Pulley puller

Removing pulley

KV99234330
(J-38873)
Pulley installer

Installing pulley

92530 89908 (for high-pressure
pipe 1)
( - )
92530 89912 (for high-pressure
flexible hose)
( - )
92530 89916 (for low-pressure
pipe 1 and low-pressure flexible
hose)
( - )
Disconnector tool set
(J-45815)

Disconnect one-touch joint connection

RJIA1875E

RJIA1876E

RJIA1877E

SJIA0285E

PREPARATION

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Tool number
(Kent-Moore No.)
Tool name

Description

HFC-134a (R-134a) refrigerant

Container color: Light blue
Container marking: HFC-134a (R-
134a)
Fitting size: Thread size

●

Large container 1/2

″

-16 ACME

KLH00-PAGS0
( - )
Nissan A/C System Oil Type S
(DH-PS)

Type: Poly alkylene glycol oil (PAG),
type S (DH-PS)
Application: HFC-134a (R-134a)
swash plate compressors (Nissan
only)

Lubricity: 40 m

(1.4 US fl oz., 1.4

Imp fl oz.)

(J-39500-INF)
Recovery/Recycling/
Recharging equipment (ACR4)

Function: Refrigerant Recovery and
Recycling and Recharging

(J-41995)
Electrical leak detector

Power supply:

●

DC 12V (Cigarette lighter)

(J-43926)
Refrigerant dye leak detection kit
Kit includes:
(J-42220)
UV lamp and UV safety goggles
(J-41459)
Refrigerant dye injector
(J-41447)
HFC-134a (R-134a) Fluorescent
leak detection dye
(Box of 24, 1/4 ounce bottles)
(J-43872)
Refrigerant dye cleaner

Power supply:
DC 12V (Battery terminal)

S-NT196

S-NT197

RJIA0195E

AHA281A

ZHA200H

ATC-18

PREPARATION

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(J-42220)
UV lamp and UV safety goggles

Power supply: DC 12V (Battery
terminal)
For checking refrigerant leak when
fluorescent dye is installed in A/C
system.
Includes: UV lamp and UV safety
goggles

(J-41447)
HFC-134a (R-134a) Fluorescent
leak detection dye
(Box of 24, 1/4 ounce bottles)

Application: For HFC-134a (R-134a)
PAG oil
Container: 1/4 ounce (7.4 cc) bottle
(Includes self-adhesive dye
identification labels for affixing to
vehicle after charging system with
dye.)

(J-41459)
HFC-134a (R-134a) Dye injector
Use with J-41447, 1/4 ounce
bottle

For injecting 1/4 ounce of fluorescent
leak detection dye into A/C system

(J-43872)
Refrigerant dye cleaner

For cleaning dye spills

(J-39183)
Manifold gauge set (with hoses
and couplers)

Identification:

●

The gauge face indicates HFC-134a
(R-134a).
Fitting size: Thread size

●

1/2

″

-16 ACME

Service hoses

●

High-pressure side hose
(J-39501-72)

●

Low-pressure side hose
(J-39502-72)

●

Utility hose
(J-39476-72)

Hose color:

●

Low hose: Blue with black stripe

●

High hose: Red with black stripe

●

Utility hose: Yellow with black stripe
or green with black stripe
Hose fitting to gauge:

●

1/2

″

-16 ACME

Tool number
(Kent-Moore No.)
Tool name

Description

SHA438F

SHA439F

SHA440F

SHA441F

RJIA0196E

S-NT201

PREPARATION

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Commercial Service Tools

AJS000YI

Service couplers

●

High-pressure side coupler
(J-39500-20)

●

Low-pressure side coupler
(J-39500-24)

Hose fitting to service hose:

●

M14 x 1.5 fitting is optional or
permanently attached.

(J-39650)
Refrigerant weight scale

For measuring of refrigerant
Fitting size: Thread size

●

1/2

″

-16 ACME

(J-39649)
Vacuum pump
(Including the isolator valve)

Capacity:

●

Air displacement: 4 CFM

●

Micron rating: 20 microns

●

Oil capacity: 482 g (17 oz.)
Fitting size: Thread size

●

1/2

″

-16 ACME

Tool number
(Kent-Moore No.)
Tool name

Description

S-NT202

S-NT200

S-NT203

Tool name

Description

Refrigerant identifier equipment

Checking for refrigerant purity and
system contamination

Power tool

Loosening bolts and nuts

RJIA0197E

PBIC0190E

ATC-20

REFRIGERATION SYSTEM

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REFRIGERATION SYSTEM

PFP:KA990

Refrigerant Cycle

AJS000YJ

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. The refrigerant evaporation through the evaporator coil is
controlled by an externally equalized expansion valve, located inside the evaporator case.

FREEZE PROTECTION

Under usual operating conditions, when the A/C is switched on, the compressor runs continuously, and the
evaporator pressure, and therefore, temperature is controlled by the compressor to prevent freeze up.

Refrigerant System Protection

AJS000YK

REFRIGERANT PRESSURE SENSOR

The refrigerant system is protected against excessively high- or low-pressure by the refrigerant pressure sen-
sor, located on the condenser. If the system pressure rises above, or falls below the specifications, the refrig-
erant pressure sensor detects the pressure inside the 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 (28 kg/cm

2

, 398 psi), or below about 134 kPa

(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 increases to an unusual level [more than 3,727 kPa(38 kg/cm

2

, 540 psi)], the release port on the pressure relief valve automatically opens and releases refrigerant into the
atmosphere.

RJIA1745E

REFRIGERATION SYSTEM

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Component Layout

AJS000YM

RJIA1746E

ATC-22

LUBRICANT

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LUBRICANT

PFP:KLG00

Maintenance of Lubricant Quantity in Compressor

AJS000YN

The lubricant in the compressor circulates through the system with the refrigerant. Add lubricant to compres-
sor when replacing any component or after a large gas leakage occurred. It is important to maintain the speci-
fied amount.
If lubricant quantity is not maintained properly, the following malfunctions may result:

●

Lack of lubricant: May lead to a seized compressor

●

Excessive lubricant: Inadequate cooling (thermal exchange interference)

LUBRICANT

LUBRICANT RETURN OPERATION

Adjust the lubricant quantity according to the test group shown below.

1.

CHECK LUBRICANT RETURN OPERATION

Can lubricant return operation be performed?

●

A/C system works properly.

●

There is no evidence of a large amount of lubricant leakage.

YES or NO

YES

>> GO TO 2.

NO

>> GO TO 3.

2.

PERFORM LUBRICANT RETURN OPERATION, PROCEEDING AS FOLLOWS:

1.

Start engine, and set the following conditions:

–

Test condition
Engine speed: Idling to 1,200 rpm
A/C switch: ON
Blower speed: Max. position
Temp. control: Optional [Set so that intake air temperature is 25 to 30

°

C (77 to 86

°

F).]

Intake position: Recirculation (REC)

2.

Perform lubricant return operation for about 10 minutes.

3.

Stop engine.

CAUTION:

If excessive lubricant leakage is noted, do not perform the lubricant return operation.

>> GO TO 3.

3.

CHECK COMPRESSOR

Should the compressor be replaced?

YES

>> GO TO

ATC-23, "LUBRICANT ADJUSTING PROCEDURE FOR COMPRESSOR REPLACE-

MENT"

.

NO

>> GO TO 4.

Name

:NISSAN A/C System Oil Type S

Part number

:KLH00-PAGS0

LUBRICANT

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4.

CHECK ANY PART

Is there any part to be replaced? (Evaporator, condenser, liquid tank or in case there is evidence of a large
amount of lubricant leakage.)

YES

>> GO TO

ATC-23, "LUBRICANT ADJUSTING PROCEDURE FOR COMPONENTS REPLACE-

MENT EXCEPT COMPRESSOR"

.

NO

>> Carry out the A/C performance test.

LUBRICANT ADJUSTING PROCEDURE FOR COMPONENTS REPLACEMENT EXCEPT COM-
PRESSOR

After replacing any of the following major components, add the correct amount of lubricant to the system.
Amount of lubricant to be added

*1:If refrigerant leak is small, no addition of lubricant is needed.

LUBRICANT ADJUSTING PROCEDURE FOR COMPRESSOR REPLACEMENT

1.

Before connecting ACR4 to vehicle, check ACR4 gauges. No refrigerant pressure should be displayed. If
NG, recover refrigerant from equipment lines.

2.

Connect ACR4 to vehicle. Confirm refrigerant purity in supply tank using ACR4 and refrigerant identifier. If
NG, refer to

ATC-6, "CONTAMINATED REFRIGERANT"

.

3.

Confirm refrigerant purity in vehicle A/C system using ACR4 and refrigerant identifier. If NG, refer to

ATC-

6, "CONTAMINATED REFRIGERANT"

.

4.

Discharge refrigerant into the refrigerant recovery/recycling equipment. Measure lubricant discharged into
the recovery/recycling equipment.

5.

Drain the lubricant from the old (removed) compressor into a graduated container and recover the amount
of lubricant drained.

6.

Drain the lubricant from the new compressor into a separate, clean container.

7.

Measure an amount of new lubricant installed equal to amount drained from old compressor. Add this
lubricant to new compressor through the suction port opening.

8.

Measure an amount of new lubricant equal to the amount recovered during discharging. Add this lubricant
to new compressor through the suction port opening.

9.

If the liquid tank also needs to be replaced, add an additional 5 m (0.2 US fl oz., 0.2 Imp fl oz.) of lubri-
cant at this time.
Do not add this 5 m (0.2 US fl oz., 0.2 Imp fl oz.) of lubricant if only replacing the compressor.

Part replaced

Lubricant to be added to system

Remarks

Amount of lubricant

m

(US fl oz., Imp fl oz.)

Evaporator

75 (2.5, 2.6)

-

Condenser

35 (1.2, 1.2)

-

Liquid tank

10 (0.3, 0.4)

-

In case of refrigerant leak

30 (1.0, 1.1)

Large leak

-

Small leak *1

ATC-24

LUBRICANT

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RHA065DD

AIR CONDITIONER CONTROL

ATC-25

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AIR CONDITIONER CONTROL

PFP:27500

Description of Air Conditioner LAN Control System

AJS000YO

The LAN (Local Area Network) system consists of unified meter and A/C amp., mode door motor, air mix door
motor and intake door motor.
A configuration of these components is shown in the figure below.

System Construction

AJS000YP

A small network is constructed between the unified meter and A/C amp., air mix door motor, mode door motor
and intake door motor. The unified meter and A/C amp. and motors are connected by data transmission lines
and motor power supply lines. The LAN network is built through the ground circuits of the each door motor.
Addresses, motor opening angle signals, motor stop signals and error checking messages are all transmitted
through the data transmission lines connecting the unified meter and A/C amp. and the each door motor.
The following functions are contained in LCUs built into the air mix door motor, mode door motor and intake
door motor.

●

Address

●

Motor opening angle signals

●

Data transmission

●

Motor stop and drive decision

●

Opening angle sensor (PBR function)

●

Comparison

●

Decision (Unified meter and A/C amp. indicated value and motor opening angle comparison)

OPERATION

The unified meter and A/C amp. receives data from each of the sensors. The unified meter and A/C amp.
sends mode door, air mix door and intake door opening angle data to the mode door motor LCU, air mix door
motor LCU and intake door motor LCU.
The mode door motor, air mix door motor and intake door motor read their respective signals according to the
address signal. Opening angle indication signals received from the unified meter and A/C amp. and each of
the motor position sensors are compared by the LCUs in each motor with the existing decision and opening
angles. Subsequently, HOT/COLD, DEFROST/VENT or FRESH/RECIRCULATION operation is selected. The
new selection data is returned to the unified meter and A/C amp.

SJIA0262E

RJIA1747E

ATC-26

AIR CONDITIONER CONTROL

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TRANSMISSION DATA AND TRANSMISSION ORDER

Unified meter and A/C amp. data is transmitted consecutively to each of the door motors following the form
shown in figure below.
Start: Initial compulsory signal sent to each of the door motors.
Address: Data sent from the unified meter and A/C amp. is selected according to data-based decisions made
by the air mix door motor, mode door motor and intake door motor.
If the addresses are identical, the opening angle data and error check signals are received by the door motor
LCUs. The LCUs then make the appropriate error decision. If the opening angle data is usual, door control
begins.
If an error exists, the received data is rejected and corrected data received. Finally, door control is based upon
the corrected opening angle data.
Opening angle:
Data that shows the indicated door opening angle of each door motor.
Error check:
Procedure by which sent and received data is checked for errors. Error data is then compiled. The error check
prevents corrupted data from being used by the air mix door motor, mode door motor and intake door motor.
Error data can be related to the following symptoms.

●

Unusual electrical frequency

●

Poor electrical connections

●

Signal leakage from transmission lines

●

Signal level fluctuation

Stop signal:
At the end of each transmission, a stop operation, in-operation, or internal error message is delivered to the
unified meter and A/C amp. This completes one data transmission and control cycle.

RJIA1748E

RJIA1749E