Nissan Pathfinder. Manual — part 677

REFRIGERATION SYSTEM SYMPTOMS

HA-19

< SYMPTOM DIAGNOSIS >

C

D

E

F

G

H

J

K

L

M

A

B

HA

N

O

P

Both high and low pressure sides
are too low.

• The area around evapora-

tor outlet does not become
cold.

• The area around evapora-

tor inlet becomes frosted.

Clogged expansion valve.
• Breakage of temperature

sensor.

• Clogging by foreign material.

Eliminate foreign material from
expansion valve or replace it.

• There is a temperature dif-

ference between the areas
around outlet and inlet
pipes of liquid tank.

• Liquid tank becomes frost-

ed.

Malfunction inside liquid tank
(clogged strainer).

Replace condenser (includes
liquid tank). Refer to

HA-38,

"CONDENSER : Removal and
Installation"

.

Evaporator becomes frosted.

Clogged or crushed low-pres-
sure pipe.

Repair or replace malfunction-
ing parts.

Malfunction in intake air tem-
perature sensor.

Check intake sensor system.
Refer to

HAC-90, "Component

Inspection"

.

There is a small temperature
difference between the high
and low pressure pipes for re-
frigerant cycle.

• Low refrigerant charge.
• Leak or leaks in A/C system.

• Check for leaks. Refer to

HA-

21, "Leak Test"

.

• Recover refrigerant, evacu-

ate system, and recharge
with the specified amount of
refrigerant. Refer to

HA-23,

"Recycle Refrigerant"

.

Low-pressure side sometimes be-
comes negative.

• Sometimes the area

around evaporator outlet
does not become cold.

• Sometimes the area

around evaporator inlet is
frosted.

• Icing caused by moisture

mixed with refrigerant.

• Deteriorated dryer material

in liquid tank.

• Recover refrigerant then re-

place condenser (includes
liquid tank). Refer to

HA-38,

"CONDENSER : Removal
and Installation"

.

• Evacuate system and re-

charge with the specified
amount of refrigerant. Refer
to

HA-23, "Charge Refriger-

ant"

.

Hunting in high-pressure side.

There is no temperature dif-
ference between high and
low-pressure sides.

Malfunctioning variable valve
in compressor.

• Replace compressor. Refer

to

HA-30, "COMPRESSOR :

Removal and Installation"

.

• Check ECV system.

Gauge indication

Refrigerant cycle

Probable cause

Corrective action

AC353A

AC354A

HA-20

< SYMPTOM DIAGNOSIS >

NOISE

NOISE

Symptom Table

INFOID:0000000009176728

Symptom

Noise source

Probable cause

Corrective action

Unusual noise from compressor
when A/C is ON.

Inside of compressor

Worn, broken, or clogged internal com-
ponents.

Check compressor oil. Re-
fer to

HA-25, "Inspection"

.

Magnet clutch

Contact of clutch disc with pulley.

Check clearance between
clutch disc and pulley.

Compressor body

Loose compressor mounting bolts.

Check torque of mounting
bolts. Refer to

HA-30, "Ex-

ploded View"

.

Unusual noise from cooler piping.

Cooler piping (pipe and
flexible hose)

Improper installation of clip and brack-
et.

Check installation of cooler
piping. Refer to

HA-34, "Ex-

ploded View"

.

Unusual noise from expansion
valve when A/C is ON.

Expansion valve

Low refrigerant charge.

• Check for leaks. Refer to

HA-21, "Leak Test"

.

• Recover refrigerant,

evacuate system, and re-
charge with the specified
amount of refrigerant.

Worn, broken, or clogged internal com-
ponents.

Eliminate foreign material
from expansion valve or re-
place it.

Unusual noise from belt.

—

Loose belt.

Check belt tension. Refer to

EM-12, "Checking Drive
Belt"

.

Damaged or broken components in-
side compressor.

Replace compressor. Refer
to

HA-30, "COMPRESSOR

: Removal and Installation"

.

REFRIGERANT

HA-21

< PERIODIC MAINTENANCE >

C

D

E

F

G

H

J

K

L

M

A

B

HA

N

O

P

PERIODIC MAINTENANCE

REFRIGERANT

Description

INFOID:0000000009176729

CONNECTION OF SERVICE TOOLS AND EQUIPMENT

Leak Test

INFOID:0000000009176730

CHECK REFRIGERANT LEAKAGE USING FLUORESCENT LEAK DETECTION DYE

1. Install a fender cover (1).
2. Wear UV safety goggles (2) provided with refrigerant dye leak detection kit.
3. Connect power cable (4) of UV lamp (6) to positive and negative terminals of the battery (3).

1.

Shut-off valve

2.

A/C service valve

3.

Recovery/recycling/recharging
equipment

4.

Refrigerant container (HFC-134a)

5.

Weight scale

6.

Vacuum pump

7.

Manifold gauge set

A.

Preferred (best) method

B.

Alternative method

C.

For charging

JSIIA0239ZZ

RJIA3815J

HA-22

< PERIODIC MAINTENANCE >

REFRIGERANT

4. Press UV lamp switch (5) and check A/C system for refrigerant leakage. (Where refrigerant leakage

occurs, fluorescent leak detection dye appears in green color.)

WARNING:

Do not look directly into UV lamp light source.

NOTE:

• For continuous operating time of UV lamp, follow the manufacturer operating instructions.

• Illuminate piping joints from different angles using UV lamp and check that there is no leakage.

• Use a mirror in area that is difficult to see to check refrigerant leakage.

• Refrigerant leakage from evaporator can be detected by soaking cotton swab or a similar material with

drain hose water and illuminating it using UV lamp.

• Dust, dirt, and packing materials adhesive used for condenser, evaporator, and other locations may flu-

oresce. Be careful not to misidentify leakage.

5. Repair or replace parts where refrigerant leakage occurs and wipe off fluorescent leak detection dye.

NOTE:

Completely wipe off fluorescent leak detection dye from gaps between parts, screw threads, and others

using a cotton swab or similar materials.

6. Use a UV lamp to check that no fluorescent leak detection dye remains after finishing work.

WARNING:

Do not look directly into UV lamp light source.

NOTE:

• For continuous operating time of UV lamp, follow the manufacturer operating instructions.

• Dust, dirt, and packing materials adhesive used for condenser, evaporator, and other locations may flu-

oresce. Be careful not to misidentify leakage.

CHECK REFRIGERANT LEAKAGE USING ELECTRONIC LEAK DETECTOR

WARNING:

Do not check refrigerant leakage while the engine is running.

CAUTION:

Be careful of the following items so that inaccurate checks or misidentifications are avoided.

• Do not allow refrigerant vapor, shop chemical vapors, cigarette smoke or others around the vehicle.

• Always check refrigerant leakage in a low air flow environment so that refrigerant may not disperse

when leakage occurs.

1. Stop the engine.
2. Connect recovery/recycling/recharging equipment or manifold gauge set to A/C service valve.
3. Check that A/C refrigerant pressure is 345 kPa (3.52 kg/cm

2

, 50 psi) or more when temperature is 16

°C

(61

°F) or more. When pressure is lower than the specified value, recycle refrigerant completely and fill

refrigerant to the specified level.

NOTE:
Leakages may not be detected if A/C refrigerant pressure is 345 kPa (3.52 kg/cm

2

, 50 psi) or less when

temperature is less than 16

°C (61°F).

4. Clean area where refrigerant leakage check is performed and check refrigerant leakage along all surfaces

of pipe connections and A/C system components using electronic leak detector probe.

CAUTION:

• Continue checking when a leakage is found. Always continue and complete checking along all

pipe connections and A/C system components for additional leakage.

• When a leakage is detected, clean leakage area using compressed air and check again.

• When checking leakage of cooling unit inside, always clean inside of drain hose so that the

probe surface may not be exposed to water or dirt.

NOTE:

• Always check leakage starting from high-pressure side and continue to low-pressure side.

• When checking leakage of cooling unit inside, operate blower fan motor for 15 minutes or more at the

maximum fan speed while the engine is stopped, and then insert electrical leak detector probe into drain

hose and hold for 10 minutes or more.

• When disconnecting shut-off valve that is connected to A/C service valve, always evacuate remaining

refrigerant so that misidentification can be avoided.

5. Repair or replace parts where refrigerant leakage is detected.
6. Start the engine and set A/C control in the following conditions.

• A/C switch ON