Nissan Pathfinder (2008 year). Manual - part 448

HAC-128

< FUNCTION DIAGNOSIS >

[MANUAL AIR CONDITIONER]

REFRIGERATION SYSTEM

REFRIGERATION SYSTEM

Refrigerant Cycle

INFOID:0000000001366829

Refer to 

HAC-128, "Refrigerant Cycle"

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Refrigerant System Protection

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Refer to 

HAC-128, "Refrigerant System Protection"

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MANUAL AIR CONDITIONER SYSTEM

HAC-129

< FUNCTION DIAGNOSIS >

[MANUAL AIR CONDITIONER]

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MANUAL AIR CONDITIONER SYSTEM

Control System Diagram

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CONTROL SYSTEM

The control system consists of input sensors, switches, the front air control (microcomputer) and outputs.
The relationship of these components is shown in the figure below:

Control System Description

INFOID:0000000001366832

CONTROL OPERATION

Front air control

AWIIA0592GB

WJIA1510E

HAC-130

< FUNCTION DIAGNOSIS >

[MANUAL AIR CONDITIONER]

MANUAL AIR CONDITIONER SYSTEM

TEMPERATURE CONTROL DIAL (TEMPERATURE CONTROL)

Increases or decreases the set temperature.

RECIRCULATION (

) SWITCH

• When REC switch is ON, REC switch indicator turns ON, and air inlet is set to REC.
• When REC switch is turned OFF, or when compressor is turned from ON to OFF, REC switch is automati-

cally turned OFF. REC mode can be re-entered by pressing REC switch again.

• REC switch is not operated when DEF switch is turned ON, or at the D/F or FOOT position.

DEFROSTER (

) SWITCH

Positions the air outlet doors to the defrost position. Also positions the intake doors to the outside air position.

REAR WINDOW DEFOGGER SWITCH

When switch is ON, rear window is defogged.

OFF SWITCH (BLOWER SPEED SET TO 0)

The compressor and blower are OFF.

A/C SWITCH

The compressor is ON or OFF.
(Pressing the A/C switch will turn off the A/C switch and compressor.)

MODE DIAL

Controls the air discharge outlets.

FRONT BLOWER CONTROL DIAL

Manually controls the four blower speeds.

MAGNET CLUTCH CONTROL

When the A/C switch is pressed, or the mode dial is turned to the DEF or D/F position, the front air control out-
puts a compressor ON signal to BCM.
The BCM then sends a compressor ON signal to ECM, via CAN communication line.
ECM judges whether compressor can be turned ON, based on each sensor status (refrigerant pressure sen-
sor signal, throttle angle sensor, etc.). If it judges compressor can be turned ON, it sends compressor ON sig-
nal to IPDM E/R, via CAN communication line.
Upon receipt of compressor ON signal from ECM, IPDM E/R turns air conditioner relay ON to operate com-
pressor.

1.

Temperature control dial

2.

Blower control dial

3.

A/C switch

4.

Rear window defogger switch

5.

Recirculation switch

6.

Mode dial

WJIA1293E

MANUAL AIR CONDITIONER SYSTEM

HAC-131

< FUNCTION DIAGNOSIS >

[MANUAL AIR CONDITIONER]

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Discharge Air Flow

INFOID:0000000001366833

Switches And Their Control Function

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SWITCHES AND THEIR CONTROL FUNCTION

Mode door position

Air outlet/distribution

Vent

Foot

Defroster

95%

5%

—

60%

40%

—

20%

55%

25%

15%

50%

35%

7%

15%

78%

Airflow always present at driver and passenger side demisters

WJIA1296E

AWIIA0271GB

HAC-132

< FUNCTION DIAGNOSIS >

[MANUAL AIR CONDITIONER]

MANUAL AIR CONDITIONER SYSTEM

WJIA1497E

CAN COMMUNICATION SYSTEM

HAC-133

< FUNCTION DIAGNOSIS >

[MANUAL AIR CONDITIONER]

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CAN COMMUNICATION SYSTEM

System Description

INFOID:0000000001366837

Refer to 

LAN-4, "System Description"

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HAC-134

< FUNCTION DIAGNOSIS >

[MANUAL AIR CONDITIONER]

DIAGNOSIS SYSTEM (BCM)

DIAGNOSIS SYSTEM (BCM)

CONSULT-III Function (BCM)

INFOID:0000000001366839

CONSULT-II can display each diagnostic item using the diagnostic test modes shown following.

DATA MONITOR

Display Item List

BCM diagnostic 

test item

Diagnostic mode

Description

Inspection by part

WORK SUPPORT

Supports inspections and adjustments. Commands are transmitted to the BCM for 
setting the status suitable for required operation, input/output signals are received 
from the BCM and received data is displayed.

DATA MONITOR

Displays BCM input/output data in real time.

ACTIVE TEST

Operation of electrical loads can be checked by sending drive signal to them.

SELF-DIAG RESULTS 

Displays BCM self-diagnosis results.

CAN DIAG SUPPORT MNTR

The result of transmit/receive diagnosis of CAN communication can be read.

ECU PART NUMBER

BCM part number can be read.

CONFIGURATION

Performs BCM configuration read/write functions.

Monitor item name “operation or 

unit”

Contents

IGN ON SW

“ON/OFF”

Displays “IGN Position (ON)/OFF, ACC Position (OFF)” status as judged from ignition switch signal.

COMP ON SIG

“ON/OFF”

Displays “COMP (ON)/COMP (OFF)” status as judged from air conditioner switch signal.

FAN ON SIG

“ON/OFF”

Displays “FAN (ON)/FAN (OFF)” status as judged from blower motor switch signal.

MODE DOOR MOTOR

HAC-135

< COMPONENT DIAGNOSIS >

[MANUAL AIR CONDITIONER]

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COMPONENT DIAGNOSIS

MODE DOOR MOTOR

System Description

INFOID:0000000001366782

SYSTEM DESCRIPTION

Component Parts

Mode door control system components are:

• Front air control
• Mode door motor
• PBR (built into mode door motor)
• Intake sensor

System Operation

The mode door position (vent, B/L, foot, D/F, and defrost) is set by the front air control by means of the mode
door motor. When a mode door position is selected on the front air control, voltage is applied to one circuit of
the mode door motor while ground is applied to the other circuit, causing the mode door motor to rotate. The
direction of rotation is determined by which circuit has voltage applied to it, and which one has ground applied
to it. The front air control monitors the mode door position by measuring the voltage signal on the PBR circuit.

COMPONENT DESCRIPTION

Mode Door Motor

The mode door motor is attached to the heater and cooling unit
assembly. It rotates so that air is discharged from the outlet as indi-
cated by the front air control. Motor rotation is conveyed to a link
which activates the mode door.

Mode Door Motor (Front) Component Function Check

INFOID:0000000001366783

SYMPTOM:

• Air outlet does not change.
• Mode door motor does not operate normally.

WJIA1314E

WJIA1484E