Nissan Pathfinder (2008 year). Manual - part 435

HAC-24

< FUNCTION DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

SELF-DIAGNOSIS FUNCTION

• Press the “BACK” switch and the “UP” switch within 10 seconds

after turning the ignition switch from OFF to ACC and hold them for
3 seconds or more. Then the buzzer sounds, all indicators of the
preset switch illuminate, and the self-diagnosis mode starts.

• The continuity of each switch and control dials (A/C and AV switch

assembly only) at the ON position can be checked by pressing
each switch and turning each control dial. The buzzer sounds and
LED's will illuminate if the switch is normal.

Finishing self-diagnosis mode

Self-diagnosis mode is canceled when turning the ignition switch OFF.

A/C System Self-Diagnosis Code Chart

INFOID:0000000001366700

SELF-DIAGNOSTIC CODE CHART

AWIIA0171GB

Code No.

Reference page

02

EE changed by calibration

VTL-8, "Removal and Installation"

03

Battery voltage out of range

CHG-10, "Inspection Procedure"

12

Passenger air mix door open/short/out of limits

HAC-37, "Air Mix Door Motor (Passenger) Diagnosis Proce-
dure"

22

Driver air mix door open/short

HAC-33, "Air Mix Door Motor (Driver) Diagnosis Procedure"

30

In-vehicle sensor circuit out of range (low)

HAC-80, "In-Vehicle Sensor Diagnosis Procedure"

31

In-vehicle sensor circuit out of range (high)

38

Air mix door motor (rear) circuit failure

HAC-61, "Rear Air Control Component Function Check"

40

Ambient sensor circuit short

HAC-77, "Ambient Sensor Diagnosis Procedure"

41

Ambient sensor circuit open

44

Intake door motor open

HAC-43, "Intake Door Motor Diagnosis Procedure"

46

Intake door motor short

50

Optical sensor (Driver) circuit open or short

HAC-83, "Optical Sensor Diagnosis Procedure"

52

Optical sensor (Passenger) circuit open or short

56

Intake sensor circuit short

HAC-157, "Intake Sensor Diagnosis Procedure"

57

Intake sensor circuit open

80

CAN bus fault

LAN-14, "Trouble Diagnosis Flow Chart"

81

BCM message missing

82

Intake door motor circuit malfunction

HAC-43, "Intake Door Motor Diagnosis Procedure"

90

Stuck button

VTL-8, "Removal and Installation"

92

Mode door motor circuit malfunction

HAC-26, "Mode Door Motor (Front) Component Function 
Check"

MODE DOOR MOTOR

HAC-25

< COMPONENT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

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COMPONENT DIAGNOSIS

MODE DOOR MOTOR

System Description

INFOID:0000000001366701

SYSTEM DESCRIPTION

Component Parts

Mode door control system components are:

• A/C auto amp.
• A/C and AV switch assembly
• Mode door motor (front)
• PBR (built into mode door motor)
• In-vehicle sensor
• Ambient sensor
• Optical sensor
• Intake sensor

System Operation

The mode door position (vent, B/L, foot, D/F, and defrost) is set by the A/C auto amp. by means of the mode
door motor (front). When a mode door position is selected on the A/C auto amp., voltage is applied to one cir-
cuit of the mode door motor (front) while ground is applied to the other circuit, causing the mode door motor
(front) 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 A/C auto amp. monitors the mode door position by measuring the voltage signal
on the PBR circuit.
In AUTO mode the mode door position is set by the A/C auto amp. which determines the proper position
based on inputs from the in-vehicle sensor, ambient sensor, optical sensor, intake sensor, and the temperature
selected by the driver or passenger.

Mode Door Control Specification

COMPONENT DESCRIPTION

Mode Door Motor (Front)

AWIIA0092GB

AWIIA0093GB

HAC-26

< COMPONENT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

MODE DOOR MOTOR

The mode door motor (front) is attached to the heater & cooling unit
assembly. It rotates so that air is discharged from the outlet as indi-
cated by the A/C auto amp. Motor rotation is conveyed to a link
which activates the mode door.

Mode Door Motor (Front) Component Function Check

INFOID:0000000001366702

INSPECTION FLOW

1.

CONFIRM SYMPTOM BY PERFORMING OPERATIONAL CHECK - DISCHARGE AIR

1.

Press mode switch four times and then press the 

 (DEF) switch. Each position indicator should change

shape (on display).

2.

Confirm that discharge air comes out according to the air distribution table. Refer to 

HAC-131, "Discharge

Air Flow"

.

NOTE:
Confirm that the compressor clutch is engaged (visual inspection) and intake door position is at FRESH

 when FOOT (

), DEF (

) or D/F (

) is selected.

Can a symptom be duplicated?

YES

>> GO TO 3.

NO

>> GO TO 2.

2.

PERFORM COMPLETE OPERATIONAL CHECK

Perform a complete operational check and check for any symptoms. Refer to 

HAC-123, "Operational Check"

.

Can a symptom be duplicated?

YES

>> Refer to 

HAC-122, "How to Perform Trouble Diagnosis For Quick And Accurate Repair"

.

NO

>> System OK.

3.

CHECK FOR SERVICE BULLETINS

Check for any service bulletins.

>> GO TO 4.

4.

CHECK MODE DOOR OPERATION

Check and verify mode door mechanism for smooth operation in each mode.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Repair as necessary.

5.

PERFORM A/C AUTO AMP. SELF-DIAGNOSIS

Perform self-diagnosis to check for any codes. Refer to 

HAC-23, "A/C Auto Amp. Self-Diagnosis"

.

Are any self-diagnosis codes present?

YES

>> Refer to 

HAC-24, "A/C System Self-Diagnosis Code Chart"

.

NO

>> GO TO 6.

6.

PERFORM A/C AND AV SWITCH ASSEMBLY SELF-DIAGNOSIS

Perform self-diagnosis to check the A/C and AV switch assembly. Refer to 

HAC-23, "A/C and AV Switch

Assembly Self-Diagnosis"

.

Is the inspection result normal?

YES

>> Replace A/C and AV switch assembly. Refer to 

VTL-8, "Removal and Installation"

.

NO

>> GO TO 6.

WJIA1084E

MODE DOOR MOTOR

HAC-27

< COMPONENT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

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7.

CHECK THE MODE DOOR MOTOR (FRONT) PBR CIRCUIT 

Perform diagnostic procedure for the mode door motor (front). Refer to 

HAC-135, "Mode Door Motor (Front)

Component Function Check"

.

Is the inspection result normal?

YES

>> GO TO 8.

NO

>> Repair PBR circuit or replace motor. Refer to 

HAC-136, "Mode Door Motor (Front) Diagnosis Pro-

cedure"

.

8.

RECHECK FOR CODES 

Perform A/C auto amp. self-diagnosis. Refer to 

HAC-23, "A/C Auto Amp. Self-Diagnosis"

.

Are any self-diagnostic codes present?

YES

>> Refer to 

HAC-24, "A/C System Self-Diagnosis Code Chart"

.

NO

>> GO TO 9.

9.

RECHECK FOR SYMPTOMS 

Perform a complete operational check and check for any symptoms. Refer to 

HAC-123, "Operational Check"

.

Does another symptom exist?

YES

>> Repair as necessary. 

NO

>> Replace A/C auto amp. Refer to 

VTL-8, "Removal and Installation"

.

Mode Door Motor (Front) Diagnosis Procedure

INFOID:0000000001366703

SYMPTOM:

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

1.

CHECK A/C AUTO AMP. FOR POWER AND GROUND 

1.

Turn ignition switch ON.

2.

Press the mode switch to the B/L (

) mode.

3.

Check voltage between A/C auto amp. harness connector M49
terminal 19 and terminal 20 while pressing the mode switch to
the floor (

) mode.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> GO TO 3.

2.

CHECK MODE DOOR MOTOR CIRCUITS FOR SHORT TO GROUND 

1.

Turn ignition switch OFF.

2.

Disconnect the A/C auto amp. harness connector.

3.

Check continuity between A/C auto amp. harness connector
M49 terminal 19, 20 and ground.

Is the inspection result normal?

YES

>> Replace A/C auto amp. Refer to 

VTL-8, "Removal and

Installation"

.

NO

>> Repair or replace harness as necessary.

Connector

Terminals

Condition 

Voltage 

(Approx.)

(+) (-)

A/C auto amp.: 

M49

20

19

Press 
mode 

switch

Battery 
voltage

AWIIA0095ZZ

19 - Ground

: Continuity should not exist.

20 - Ground

: Continuity should not exist.

AWIIA0096ZZ

HAC-28

< COMPONENT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

MODE DOOR MOTOR

3.

CHECK A/C AUTO AMP. FOR GROUND AND POWER 

1.

Press the mode switch to the D/F (

) mode.

2.

Check voltage between A/C auto amp. harness connector M49
terminal 19 and terminal 20 while pressing the mode switch to
the vent (

) mode.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Replace A/C auto amp. Refer to 

VTL-8, "Removal and Installation"

.

4.

CHECK MODE DOOR MOTOR AND CIRCUITS FOR OPEN

1.

Turn ignition switch OFF.

2.

Disconnect the A/C auto amp. harness connector.

3.

Check continuity between A/C auto amp. harness connector
M49 terminal 19 and terminal 20.

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> GO TO 6.

5.

CHECK MODE DOOR MOTOR CIRCUITS FOR OPEN 

1.

Disconnect the mode door motor harness connector.

2.

Check continuity between A/C auto amp. harness connector
M49 (A) terminal 19, 20 and the mode door motor harness con-
nector M142 (B) terminal 1, 6.

Is the inspection result normal?

YES

>> Replace mode door motor. Refer to 

VTL-28, "Removal

and Installation"

.

NO

>> Repair or replace harness as necessary.

6.

CHECK A/C AUTO AMP. FOR PBR POWER AND GROUND

1.

Reconnect A/C auto amp. harness connector.

2.

Turn ignition switch ON.

3.

Check voltage between A/C auto amp. harness connector M50
(A) terminal 28 and M49 (B) terminal 3.

Is the inspection result normal?

YES

>> GO TO 9.

NO

>> GO TO 8.

7.

CHECK PBR REFERENCE VOLTAGE CIRCUIT FOR SHORT TO GROUND

Connector

Terminals

Condition 

Voltage 

(Approx.)

(+) (-)

A/C auto amp.: 

M49

19 20

Press 
mode 

switch

Battery 
voltage

AWIIA0097ZZ

Continuity should exist.

AWIIA0098ZZ

6 - 19

: Continuity should exist.

1 - 20

: Continuity should exist.

AWIIA0225ZZ

Connector

Terminals

Voltage (Ap-

prox.)

(+)

(-)

A/C auto amp.: M49, M50

28 

3

5V

AWIIA0099ZZ

MODE DOOR MOTOR

HAC-29

< COMPONENT DIAGNOSIS >

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1.

Turn ignition switch OFF.

2.

Disconnect the A/C auto amp. harness connector.

3.

Check continuity between A/C auto amp. harness connector
M50 terminal 28 and ground.

Is the inspection result normal?

YES

>> Replace A/C auto amp. Refer to 

VTL-8, "Removal and

Installation"

.

NO

>> Repair or replace harness as necessary.

8.

CHECK PBR REFERENCE VOLTAGE AND GROUND CIRCUITS

1.

Turn ignition switch OFF.

2.

Disconnect the A/C auto amp. harness connector.

3.

Check continuity between A/C auto amp. harness connector
M50 (A) terminal 28 and M49 (B) terminal 3.

Is the inspection result normal?

YES

>> GO TO 11.

NO

>> GO TO 10

9.

CHECK PBR REFERENCE VOLTAGE CIRCUIT FOR OPEN

1.

Disconnect the mode door motor harness connector.

2.

Check continuity between mode door motor harness connector
M142 (B) terminal 3, 1 and A/C auto amp. harness connector
M49 (C) terminal 3, M50 (A) terminal 28.

Is the inspection result normal?

YES

>> Replace mode door motor. Refer to 

VTL-28, "Removal

and Installation"

.

NO

>> Repair or replace harness as necessary.

10.

CHECK PBR FEEDBACK VOLTAGE

1.

Reconnect the A/C auto amp. harness connector.

2.

Turn ignition switch ON.

3.

Check voltage between A/C auto amp. harness connector M49
terminal 7 and ground while cycling mode switch through all
modes.

Is the inspection result normal?

YES

>> GO TO 13.

NO

>> GO TO 12.

11.

CHECK PBR FEEDBACK SIGNAL CIRCUIT FOR SHORT TO GROUND

Continuity should not exist.

AWIIA0100ZZ

Continuity should exist.

AWIIA0101ZZ

28 - 3

: Continuity should exist.

3 - 2

: Continuity should exist.

AWIIA0226ZZ

 Voltage

: Approx. 1V - 4.5V

AWIIA0103ZZ

HAC-30

< COMPONENT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

MODE DOOR MOTOR

1.

Turn ignition switch OFF.

2.

Disconnect A/C auto amp. harness connector.

3.

Check continuity between A/C auto amp. harness connector
M49 terminal 7 and ground.

Is the inspection result normal?

YES

>> Replace A/C auto amp. Refer to 

VTL-8, "Removal and

Installation"

.

NO

>> Repair or replace harness as necessary.

12.

CHECK PBR FEEDBACK CIRCUIT FOR OPEN

1.

Turn ignition switch OFF.

2.

Disconnect the mode door motor harness connector and A/C
auto amp. harness connector.

3.

Check continuity between mode door motor harness connector
M142 terminal 4 and A/C auto amp. harness connector M49 ter-
minal 7.

Is the inspection result normal?

YES

>> Replace mode door motor. Refer to 

VTL-28, "Removal

and Installation"

.

NO

>> Repair or replace harness as necessary.

Continuity should not exist.

AWIIA0104ZZ

Continuity should exist.

AWIIA0227ZZ

AIR MIX DOOR MOTOR

HAC-31

< COMPONENT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

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AIR MIX DOOR MOTOR

System Description

INFOID:0000000001366704

SYSTEM DESCRIPTION

SYMPTOM:

• Discharge air temperature does not change.
• Air mix door motor does not operate.

SYSTEM DESCRIPTION

Component Parts

Air mix door control system components are:

• A/C auto amp.
• A/C and AV switch assembly
• Air mix door motors (driver, passenger, and rear)
• PBR (built-into air mix door motors)
• In-vehicle sensor
• Ambient sensor
• Optical sensor
• Intake sensor

System Operation

The A/C auto amp. receives data from the temperature selected by the driver side, passenger side, and rear.
The A/C auto amp. then applies a voltage to one circuit of the appropriate air mix door motor, while ground is
applied to the other circuit, causing the appropriate air mix 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 A/C auto
amp. monitors the air mix door positions by measuring the voltage signal on the PBR circuits of each door.
In AUTO mode the air mix, intake, mode door, and defrost door positions are set by the A/C auto amp. which
determines the proper position based on inputs from the in-vehicle sensor, ambient sensor, optical sensor,
intake sensor, and the temperature selected by the driver and front and rear passengers.
Subsequently, HOT/COLD or DEFROST/VENT or FRESH/RECIRCULATION operation is selected. The new
door position data is returned to the A/C auto amp.

AWIIA0106GB