Nissan Leaf. Manual - part 742

HA-90

< BASIC INSPECTION >

[WITHOUT HEAT PUMP SYSTEM]

PERFORMANCE TEST

INTAKE –DISCHARGE

JSIIA1640GB

PERFORMANCE TEST

HA-91

< BASIC INSPECTION >

[WITHOUT HEAT PUMP SYSTEM]

C

D

E

F

G

H

J

K

L

M

A

B

HA

N

O

P

AMBIENT TEMPERATURE–PRESSURE CHARACTERISTICS

JSIIA1641GB

HA-92

< SYMPTOM DIAGNOSIS >

[WITHOUT HEAT PUMP SYSTEM]

REFRIGERATION SYSTEM SYMPTOMS

SYMPTOM DIAGNOSIS

REFRIGERATION SYSTEM SYMPTOMS

Trouble Diagnosis For Unusual Pressure

INFOID:0000000010122166

Diagnose using a manifold gauge whenever system’s high and/or low side pressure(s) is/are unusual. The

marker above the gauge scale in the following tables indicates the standard (usual) pressure range. Refer to

above table (Ambient air temperature-to-operating pressure table) since the standard (usual) pressure, how-

ever, differs from vehicle to vehicle.

Symptom Table

INFOID:0000000010122167

Gauge indication

Refrigerant cycle

Probable cause

Corrective action

Both high- and low-pressure sides 
are too high.

The pressure returns to nor-
mal soon after sprinkling wa-
ter on condenser.

Overfilled refrigerant.

Collect all refrigerant, evacuate 
refrigerant cycle again, and 
then refill it with the specified 
amount of refrigerant.

Air flow to condenser is insuf-
ficient.

Insufficient condenser cooling 
performance.
• Poor fan rotation of radiator 

and condenser.

• Improper installation of air 

guide.

• Clogged or dirty condenser 

fins.

• Repair or replace malfunc-

tioning parts.

• Clean and repair condenser 

fins.

When compressor is stopped, 
a high-pressure reading 
quickly drops by approximate-
ly 196 kPa (2 kg/cm

2

, 28.4 

psi). It then gradually de-
creases.

Air mixed in refrigerant cycle.

Collect all refrigerant, evacuate 
refrigerant cycle again, and 
then refill it with the specified 
amount of refrigerant.

• Low-pressure pipe is cooler 

than the outlet of evapora-
tor.

• Low-pressure pipe is frost-

ed.

Expansion valve opened too 
much (excessive flow of refrig-
erant).

Replace expansion valve.

High-pressure side is excessively 
high and low-pressure side is too 
low.

High-pressure pipe and upper 
side of condenser become 
hot, however, liquid tank does 
not become so hot.

Clogged or crushed high-pres-
sure pipe located between 
compressor and condenser.

Repair or replace the malfunc-
tioning parts.

High-pressure side is too low and 
low-pressure side is too high.

• The readings of both sides 

become equal soon after 
compressor operation 
stops.

• There is no temperature dif-

ference between high- and 
low-pressure sides.

Malfunction in compressor sys-
tem (insufficient compressor 
pressure operation).
• Damage or breakage of 

valve.

• Malfunctioning gaskets.

Replace compressor.

AC359A

AC360A

AC356A

REFRIGERATION SYSTEM SYMPTOMS

HA-93

< SYMPTOM DIAGNOSIS >

[WITHOUT HEAT PUMP SYSTEM]

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 liquid tank.

Evaporator becomes frosted.

Clogged or crushed low-pres-
sure pipe.

Repair or replace malfunction-
ing parts.

Malfunction in intake sensor.

Check intake sensor system. 
Refer to 

HAC-286, "Diagnosis 

Procedure"

.

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

• Shortage of refrigerant.
• Leakage of refrigerant.

• Check for leakage.
• Collect all refrigerant, evacu-

ate refrigerant cycle again, 
and then refill it with the spec-
ified amount of 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 the mixing of 

water in cooler cycle.

• Deteriorated dryer in liquid 

tank.

• Collect all refrigerant.
• Evacuate refrigerant cycle 

completely, and then refill it 
with the specified amount of 
refrigerant. At this time, al-
ways replace liquid tank.

Gauge indication

Refrigerant cycle

Probable cause

Corrective action

AC353A

AC354A