Nissan Pathfinder (2012 year). Manual - part 421

HAC-90

< DTC/CIRCUIT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

POWER SUPPLY AND GROUND CIRCUIT FOR CONTROLLER

POWER SUPPLY AND GROUND CIRCUIT FOR CONTROLLER

Component Description

INFOID:0000000007356396

COMPONENT DESCRIPTION

A/C auto amp.

The A/C auto amp. (1) has a built-in microcomputer which processes

information sent from various sensors needed for air conditioner

operation. The air mix door motors, mode door motor, intake door

motor, defroster door motor, blower motor and compressor are then

controlled.

The A/C auto amp. is unitized with control mechanisms. When the

various switches and temperature dials are operated, data is input to

the A/C auto amp. 

Self-diagnostic functions are also built into the A/C auto amp. to pro-

vide quick check of malfunctions in the auto air conditioner system.

Potentio Temperature Control (PTC)

There are two PTCs (driver and passenger) built into the A/C auto

amp. They can be set at an interval of 0.5

°

C (1.0

°

F) in the 18

°

C

(60

°

F) to 32

°

C (90

°

F) temperature range by rotating the temperature

dial. The set temperature is displayed.

A/C Auto Amp. Component Function Check

INFOID:0000000007356397

SYMPTOM: A/C system does not come on.

INSPECTION FLOW

1.

CONFIRM SYMPTOM BY PERFORMING OPERATIONAL CHECK - AUTO MODE

1. Press AUTO switch.

2. Display should indicate AUTO. Confirm that the compressor clutch engages (sound or visual inspection).

(Discharge air and blower speed will depend on ambient, in-vehicle and set temperatures.) 

Is the inspection result normal?

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-5, "Operational Check

(Front)"

 or 

HAC-6, "Operational Check (Rear)"

.

Is the inspection result normal?

YES

>> Refer to 

HAC-128, "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 POWER AND GROUND CIRCUIT

AWIIA0170ZZ

AWIIA0211GB

August 2012

2012 Pathfinder

POWER SUPPLY AND GROUND CIRCUIT FOR CONTROLLER

HAC-91

< DTC/CIRCUIT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

C

D

E

F

G

H

J

K

L

M

A

B

HAC

N

O

P

Check main power supply and ground circuit. Refer to 

HAC-91, "A/C Auto Amp Power and Ground Diagnosis

Procedure"

.

Is the inspection result normal?

YES

>> System OK.

NO

>> Replace A/C auto amp. Refer to 

VTL-7, "Removal and Installation"

. 

A/C Auto Amp Power and Ground Diagnosis Procedure

INFOID:0000000007356398

Regarding Wiring Diagram information, refer to 

HAC-95, "Wiring Diagram - Automatic"

.

DIAGNOSTIC PROCEDURE FOR A/C SYSTEM

SYMPTOM: A/C system does not come on.

1.

 CHECK POWER SUPPLY CIRCUITS FOR A/C AUTO AMP.

1. Disconnect A/C auto amp. connectors.

2. Check voltage between A/C auto amp. harness connector M49

(B) terminal 15 and M50 (A) terminal 27, and ground.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Check 10A fuses [Nos. 8 and 19, located in the fuse block (J/B)]. Refer to 

HAC-93, "A/C Auto

Amp. Terminals Reference Values"

.

• If fuses are OK, check harness for open circuit. Repair or replace as necessary.

• If fuses are NG, replace fuse and check harness for short circuit. Repair or replace as neces-

sary.

2.

 CHECK GROUND CIRCUIT FOR A/C AUTO AMP.

AWIIA0212GB

Terminals

Ignition switch position

(+)

(-)

OFF

ACC

ON

A/C auto 

amp. con-

nector

Terminal No.

M49

15 

Ground

Approx. 0V

Approx. 0V

Battery 
voltage

M50

27

Battery 
voltage

Battery 
voltage

Battery 
voltage

AWIIA1047ZZ

August 2012

2012 Pathfinder

HAC-92

< DTC/CIRCUIT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

POWER SUPPLY AND GROUND CIRCUIT FOR CONTROLLER

1. Turn ignition switch OFF.

2. Check continuity between A/C auto amp. harness connector

M50 terminal 36 and ground.

Is the inspection result normal?

OK

>> Replace A/C auto amp. Refer to 

VTL-7, "Removal and

Installation"

.

NG

>> Repair harness or connector.

36 - Ground

: Continuity should exist.

AWIIA0214ZZ

August 2012

2012 Pathfinder

AIR CONDITIONER CONTROL

HAC-93

< ECU DIAGNOSIS INFORMATION >

[AUTOMATIC AIR CONDITIONER]

C

D

E

F

G

H

J

K

L

M

A

B

HAC

N

O

P

ECU DIAGNOSIS INFORMATION

AIR CONDITIONER CONTROL

A/C Auto Amp. Terminals Reference Values

INFOID:0000000007356399

Measure voltage between each terminal and ground by following

Terminals and Reference Value for A/C auto amp. (1).

A/C AUTO AMP. HARNESS CONNECTOR TERMINAL LAYOUT

TERMINALS AND REFERENCE VALUES FOR A/C AUTO AMP. 

AWIIA0170ZZ

AWIIA0840ZZ

Terminal 

No.

Wire 

color

Item

Ignition 

switch

Condition

Voltage (V)

(Approx.)

1

G

Optical sensor (driver)

ON

-

0 - 5V

2

L

Air mix door motor (passenger) CCW

ON

-

0 - 5V

3

G

V ref ACTR (ground)

ON

-

 5V

4

W

Compressor ON signal

ON

A/C switch OFF

5V

ON

A/C switch ON

0V

5

R

Fan ON signal

ON

Blower switch OFF

5V

ON

Blower switch ON

0V

6

SB

Air mix door motor (driver) feedback

ON

-

0 - 5V

7

V

Mode door motor (front) feedback

ON

-

0 - 5V

8

G

Illumination +

ON

Park lamps ON

Battery voltage

9

BR

Illumination -

-

Park lamps ON

11

L

Intake sensor

ON

-

0 - 5V

12

P

Variable blower control (rear)

ON

-

0 - 5V

13

R

Variable blower control (front)

ON

Blower speed (low)

1.7V

Blower speed (high)

4.5V

PIIA2344E

August 2012

2012 Pathfinder

HAC-94

< ECU DIAGNOSIS INFORMATION >

[AUTOMATIC AIR CONDITIONER]

AIR CONDITIONER CONTROL

14

LG

Air mix door motor (passenger) CW

ON

Clockwise rotation

Battery voltage

15

W/G

Power supply for IGN

ON

-

Battery voltage

17

GR

Air mix door motor (driver) CW

ON

Clockwise rotation

Battery voltage

18

BR

Air mix door motor (driver) CCW

ON

Counterclockwise rotation

Battery voltage

19

L

Mode door motor CW (front)

ON

Clockwise rotation

Battery voltage

20

B/R

Mode door motor CCW

ON

Counterclockwise rotation

Battery voltage

21

O

Intake door motor CCW

ON

Counterclockwise rotation

Battery voltage

22

O

Intake door motor CW

ON

Clockwise rotation

Battery voltage

25

W

Ambient sensor

ON

-

0 - 5V

26

V

Sensor ground

ON

-

0V

27

R/Y

Power supply for BAT

-

-

Battery voltage

28

P

V ref ACTR (5V)

ON

-

0 - 5V

29

SB

Air mix door motor (passenger) feed-
back

ON

-

0 - 5V

30

R

Air mix door motor (Rear) feedback

ON

-

0 - 5V

31

BR

In-vehicle sensor motor (+)

ON

-

Battery voltage

32

LG

In-vehicle sensor signal

ON

-

0 - 5V

34

GY

Front aux backlight dim 

ON

Headlamps OFF

Battery voltage

35

W/G

Front aux tell tale LED

ON

Tell tale OFF

Battery voltage

36

B

Ground

-

-

0V

37

GR

Front aux temp pot

ON

Rear air control (front) tem-
perature control dial

0 - 5V

38

P

Front aux blower pot

ON

Rear air control (front) 
blower motor

0 - 5V

39

SB

Front AUX (rear)

ON

-

0 - 5V

40

P

CAN-L

ON

-

0 - 5V

41

L

CAN-H

ON

-

0 - 5V

42

GR

Optical sensor (passenger)

ON

-

0 - 5V

43

V

Air mix door motor (Rear) CW

ON

Clockwise rotation

Battery voltage

44

O

Air mix door motor (Rear) CCW

ON

Counterclockwise rotation

Battery voltage

45

P

Water valve (VK56DE)

ON

Water valve open

Battery voltage

Water valve closed

0V

46

R

Water valve (VK56DE)

ON

Water valve open

0V

Water valve closed

Battery voltage

50

GR

Heater pump request (VQ40DE)

ON

Heater pump on

0V

Heater pump off

Battery voltage

51

L

Rear aux temp pot

ON

Rear air control (rear) tem-
perature control dial

0 - 5V

52

W

Rear aux blower pot

ON

Rear blower motor

0 - 5V

Terminal 

No.

Wire 

color

Item

Ignition 

switch

Condition

Voltage (V)

(Approx.)

August 2012

2012 Pathfinder

AIR CONDITIONER CONTROL

HAC-95

< WIRING DIAGRAM >

[AUTOMATIC AIR CONDITIONER]

C

D

E

F

G

H

J

K

L

M

A

B

HAC

N

O

P

WIRING DIAGRAM

AIR CONDITIONER CONTROL

Wiring Diagram - Automatic

INFOID:0000000007356400

ABIWA0083GB

August 2012

2012 Pathfinder

HAC-96

< WIRING DIAGRAM >

[AUTOMATIC AIR CONDITIONER]

AIR CONDITIONER CONTROL

ABIWA0080GB

August 2012

2012 Pathfinder

AIR CONDITIONER CONTROL

HAC-97

< WIRING DIAGRAM >

[AUTOMATIC AIR CONDITIONER]

C

D

E

F

G

H

J

K

L

M

A

B

HAC

N

O

P

ABIWA0224GB

August 2012

2012 Pathfinder