Nissan Altima L32. Manual - part 828

HAC-86

< SYMPTOM DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

INSUFFICIENT COOLING

*1

HA-27, "Checking System for Leaks 
Using the Fluorescent Leak Detector"

*2

HA-35, "Removal and Installation for 
Compressor - QR25DE Models"

 or 

HA-36, "Removal and Installation for 
Compressor - VQ35DE Models"

*3

HAC-87, "Performance Chart"

*4

HAC-88, "Trouble Diagnosis For Ab-
normal Pressure"

*5

HAC-35, "Diagnosis Procedure"

AWIIA0999GB

INSUFFICIENT COOLING

HAC-87

< SYMPTOM DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

C

D

E

F

G

H

J

K

L

M

A

B

HAC

N

O

P

Performance Chart

INFOID:0000000004498236

TEST CONDITION

Testing must be performed as follows:

*1

VTL-15, "Removal and Installation"

*2

HAC-42, "Diagnosis Procedure"

*3

HAC-47, "Diagnosis Procedure"

*4

EM-16, "Checking Drive Belts"

 

(QR25DE) or 

EM-121, "Checking Drive Belts"

 

(VQ35DE)

*5

HA-35, "Removal and Installation for 
Compressor - QR25DE Models"

 or 

HA-36, "Removal and Installation for 
Compressor - VQ35DE Models"

AWIIA1240GB

HAC-88

< SYMPTOM DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

INSUFFICIENT COOLING

TEST READING

Recirculating-to-discharge Air Temperature Table

Ambient Air Temperature-to-operating Pressure Table

Trouble Diagnosis For Abnormal Pressure

INFOID:0000000004498237

Whenever system's high and/or low side pressure is abnormal, diagnose using a manifold gauge. The marker

above the gauge scale in the following tables indicates the standard (normal) pressure range. Since the stan-

dard (normal) pressure differs from vehicle to vehicle, refer to Ambient Air Temperature-to-operating Pressure

Table above.

Both High- and Low-pressure Sides are Too High

Vehicle location

Indoors or in the shade (in a well-ventilated place)

Doors

Closed

Door windows

Open

Hood

Open

TEMP.

Max. COLD

Mode switch

(Ventilation) set

Intake switch

(Recirculation) set

(blower) speed

Max. speed set

Engine speed

Idle speed

Operate the air conditioning system for 10 minutes before taking measurements.

Inside air (Recirculating air) at blower assembly inlet

Discharge air temperature at center ventilator

°C (°F)

Relative humidity

%

Air temperature

°C (°F)

50 - 60

25 (77)

10.0 - 12.3 (50 - 54)

30 (86)

13.2 - 15.3 (56 - 60)

35 (95)

17.2 - 21.0 (63 - 70)

60 - 70

25 (77)

12.3 - 14.9 (54 - 59)

30 (86)

15.3 - 19.3 (60 - 67)

35 (95)

21.0 - 24.4 (70 - 76)

Ambient air

High-pressure (Discharge side)

kPa (kg/cm2, psi)

Low-pressure (Suction side)

kPa (kg/cm2, psi)

Relative humidity

%

Air temperature

°C (°F)

50 - 70

30 (86)

1,220 - 1,500
(12.44 - 15.30, 176.9 - 217.5)

240 - 295
(2.45 - 3.01, 34.8 - 42.8)

35 (95)

1,360 - 1,690
(13.87 - 17.24, 197.2 - 245.1)

275 - 335
(2.81 - 3.42, 39.9 - 48.6)

40 (104)

1,500 - 1,830
(12.44 - 18.67, 176.9 - 265.4)

310 - 375
(3.16 - 3.83, 45.0 - 54.4)

INSUFFICIENT COOLING

HAC-89

< SYMPTOM DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

C

D

E

F

G

H

J

K

L

M

A

B

HAC

N

O

P

High-pressure Side is Too High and Low-pressure Side is Too Low

High-pressure Side is Too Low and Low-pressure Side is Too High

Gauge indication

Refrigerant cycle

Probable cause

Corrective action

Both high and low-pressure 
sides are too high.

Pressure is reduced soon after 
water is splashed on condens-
er.

Excessive refrigerant charge in 
refrigeration cycle

Reduce refrigerant until speci-
fied pressure is obtained.

Air suction by cooling fan is in-
sufficient.

Insufficient condenser cooling 
performance
↓
1.

Condenser fins are 
clogged.

2.

Improper fan rotation of 
cooling fan

• Clean condenser.
• Check and repair cooling fan 

as necessary.

• Low-pressure pipe is not 

cold.

• When compressor is stopped 

high-pressure value quickly 
drops by approximately 196 
kPa (2 kg/cm

2

, 28 psi). It then 

decreases gradually thereaf-
ter.

Poor heat exchange in con-
denser
(After compressor operation 
stops, high pressure decreases 
too slowly.)
↓
Air in refrigeration cycle

Evacuate and recharge system.

Engine tends to overheat.

Engine cooling systems mal-
function.

Check and repair each engine 
cooling system.

• An area of the low-pressure 

pipe is colder than areas near 
the evaporator outlet.

• Plates are sometimes cov-

ered with frost.

• Excessive liquid refrigerant 

on low-pressure side

• Excessive refrigerant dis-

charge flow

• Expansion valve is open a lit-

tle compared with the specifi-
cation.

↓
1.

Improper thermal valve in-
stallation

2.

Improper expansion valve 
adjustment

Replace expansion valve.

AC359A

Gauge indication

Refrigerant cycle

Probable cause

Corrective action

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

Upper side of condenser and 
high-pressure side are hot, 
however, liquid tank is not so 
hot.

High-pressure tube or parts lo-
cated between compressor 
and condenser are clogged or 
crushed.

• Check and repair or replace 

malfunctioning parts.

• Check lubricant for contami-

nation.

AC360A