Nissan Pathfinder (2008 year). Manual — part 438

HAC-48

< COMPONENT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

BLOWER MOTOR CONTROL SYSTEM

Check 15A fuses [No. 24 and 27 (Located in the fuse and fusible link box)].

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> GO TO 9.

2.

CHECK FRONT BLOWER MOTOR POWER SUPPLY CIRCUIT

1.

Turn ignition switch OFF.

2.

Disconnect front blower motor connector.

3.

Turn ignition switch ON.

4.

Press the A/C switch.

5.

Press the front blower control "+" switch to maximum speed.

6.

Check voltage between front blower motor harness connector
M62 terminal 2 and ground.

Is the inspection result normal?

YES

>> GO TO 10.

NO

>> GO TO 3.

3.

CHECK FRONT BLOWER MOTOR RELAY (SWITCH SIDE) POWER SUPPLY CIRCUIT

1.

Turn ignition switch OFF.

2.

Disconnect front blower motor relay.

3.

Check voltage between front blower motor relay harness con-
nector E22 terminals 5, 7 and ground.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Repair harness or connector.

4.

CHECK FRONT BLOWER MOTOR RELAY

Turn ignition switch OFF.
Check front blower motor relay. Refer to

HAC-151, "Front Blower Motor Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Replace front blower motor relay.

5.

CHECK FRONT BLOWER MOTOR RELAY (SWITCH SIDE) CIRCUIT FOR OPEN

Check continuity between front blower motor relay harness connec-
tor E22 terminals 3, 6 and front blower motor harness connector
M62 terminal 2.

Is the inspection result normal?

YES

>> GO TO 6.

NO

>> Repair harness or connector.

6.

CHECK VARIABLE BLOWER CONTROL POWER SUPPLY CIRCUIT FOR OPEN

Fuses are good.

2 - Ground

: Battery voltage

WJIA1331E

5 - Ground

: Battery voltage

7 - Ground

: Battery voltage

WJIA1634E

3, 6 - 2

: Continuity should exist.

WJIA1333E

BLOWER MOTOR CONTROL SYSTEM

HAC-49

< COMPONENT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

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1.

Disconnect variable blower control harness connector.

2.

Check continuity between front blower motor relay harness con-
nector E22 (A) terminals 3, 6 and variable blower control har-
ness connector M122 (B) terminal 4.

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> Repair harness or connector.

7.

CHECK VARIABLE BLOWER CONTROL SIGNAL CIRCUIT

1.

Disconnect A/C auto amp. connector.

2.

Check continuity between A/C auto amp. harness connector
M49 (B) terminal 13 and variable blower control harness con-
nector M122 (A) terminal 3.

Is the inspection result normal?

YES

>> GO TO 8.

NO

>> Repair harness or connector.

8.

CHECK FRONT BLOWER MOTOR RELAY (COIL SIDE) POWER SUPPLY

1.

Turn ignition switch ON.

2.

Check voltage between front blower motor relay harness con-
nector E22 terminal 1 and ground.

Is the inspection result normal?

YES

>> GO TO 9.

NO

>> Repair front blower motor ground circuit or connector.

9.

REPLACE FUSES

1.

Replace fuses.

2.

Activate the front blower motor.

Does the fuse blow?

YES

>> GO TO 10.

NO

>> Inspection End.

10.

CHECK FRONT BLOWER MOTOR POWER SUPPLY CIRCUIT FOR SHORT

1.

Turn ignition switch OFF.

2.

Disconnect front blower motor connector and variable blower
control connector.

3.

Check continuity between variable blower control harness con-
nector M122 terminal 4 and ground.

Is the inspection result normal?

YES

>> GO TO 11.

NO

>> Repair harness or connector.

11.

CHECK VARIABLE BLOWER CONTROL SIGNAL CIRCUIT

3, 6 - 4

: Continuity should exist.

AWIIA0243ZZ

13 - 3

: Continuity should exist.

AWIIA0176ZZ

1 - Ground

: Battery voltage

WJIA0504E

4 - Ground

: Continuity should not exist.

AWIIA0177ZZ

HAC-50

< COMPONENT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

BLOWER MOTOR CONTROL SYSTEM

1.

Disconnect A/C auto amp. connector.

2.

Check continuity between A/C auto amp. harness connector
M49 (B) terminal 13 and variable blower control harness con-
nector M122 (A) terminal 3.

Is the inspection result normal?

YES

>> GO TO 12.

NO

>> Repair harness or connector.

12.

CHECK FRONT BLOWER MOTOR

Check front blower motor. Refer to

HAC-151, "Front Blower Motor Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 13.

NO

>> Replace front blower motor. Refer to

VTL-13, "Removal and Installation"

.

13.

CHECK BLOWER MOTOR GROUND CIRCUIT

Check continuity between front blower motor harness connector
M62 terminal 1 and variable blower control harness connector M122
terminal 2.

Is the inspection result normal?

YES

>> GO TO 14.

NO

>> Repair harness or connector.

14.

CHECK VARIABLE BLOWER CONTROL GROUND CIRCUIT

Check continuity between variable blower control harness connector
M122 terminal 1 and ground.

Is the inspection result normal?

YES

>> Replace variable blower control. Refer to

VTL-15,

"Removal and Installation"

.

NO

>> Repair harness or connector.

Front Blower Motor Component Inspection

INFOID:0000000001366717

COMPONENT INSPECTION

Front Blower Relay

13 - 3

: Continuity should exist.

AWIIA0178ZZ

1 - 2

: Continuity should exist.

AWIIA0179ZZ

1 - Ground

: Continuity should exist.

AWIIA0180ZZ

BLOWER MOTOR CONTROL SYSTEM

HAC-51

< COMPONENT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

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Check continuity between terminals 6-7 and 3-5 by supplying 12
volts to terminal 1 and ground to terminal 2 of relay.

Front Blower Motor

Confirm smooth rotation of the blower motor.
• Ensure that there are no foreign particles inside the blower unit.
• Apply 12 volts to terminal 2 and ground to terminal 1 and verify that

the motor operates freely and quietly.

Rear Blower Motor Description

INFOID:0000000001366718

SYSTEM DESCRIPTION

Component Parts

Rear blower speed control system components are:
• A/C auto amp.
• A/C and AV switch assembly
• Rear air control (front)
• Rear air control (rear)
• Variable blower control (rear)
• Rear blower motor
• Rear blower motor relay

LJIA0068E

WJIA1508E

HAC-52

< COMPONENT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

BLOWER MOTOR CONTROL SYSTEM

System Operation

Rear Blower Control

When the rear blower control dial (front) REAR CTRL switch is pressed (indicator on), it allows the rear air
control (rear) to control the rear blower motor speed. If the REAR CTRL switch is off (indicator off), the rear air
control (front) controls the rear blower motor speed regardless of the rear air control (rear) position.

Rear Blower motor Component Function Check

INFOID:0000000001366719

SYMPTOM:
• Rear blower motor does not operate from the rear air control (front) and the rear air control (rear).
• Rear blower motor operates from rear air control (front) only.
• Rear blower motor operates from rear air control (rear) only.
• Rear blower motor speed does not match the rear air control (front) speed selected.
• Rear blower motor speed does not match the rear air control (rear) speed selected.
• Rear blower motor operates in high all the time when controlled from the rear air control (front).
• Rear blower motor operates in high all the time when controlled from the rear air control (rear).

INSPECTION FLOW

1.

CONFIRM SYMPTOM BY PERFORMING OPERATIONAL CHECK - REAR AIR CONTROL (FRONT)

1.

Press AUTO switch.

2.

Turn the rear air control (front) blower control dial to the lowest speed and check for rear blower operation
(REAR CTRL indicator off).

3.

Continue checking that rear blower speed increases as the rear blower control dial is rotated clockwise.

Does the rear blower motor operate correctly?

YES

>> GO TO 3.

NO

>> GO TO 2.

2.

CONFIRM SYMPTOM BY PERFORMING OPERATIONAL CHECK - REAR AIR CONTROL (REAR)

1.

Press the REAR CTRL switch (indicator on) on the rear air control (front) to send control of the rear blower
motor back the rear air control (rear).

2.

Turn the rear air control (rear) blower control dial to the lowest speed and check for rear blower operation.

3.

Continue checking that rear blower speed increases as the rear blower control dial is rotated clockwise.

Does the rear blower motor operate correctly?

YES

>> • Rear blower motor does not operate at any speed from the rear air control (front). Refer to

HAC-

53, "Rear Air Control (Front) Diagnosis Procedure #1"

.

• Rear blower motor operates in high speed all the time or does not match the rear air control

(front) speed selected. Refer to

HAC-54, "Rear Air Control (Rear) Diagnosis Procedure #2"

.

NO

>> • Rear blower motor does not operate from the rear air control (front) and the rear air control

(rear). Refer to

HAC-55, "Rear Air Control (Rear) Diagnosis Procedure #3"

3.

CONFIRM SYMPTOM BY PERFORMING OPERATIONAL CHECK - REAR AIR CONTROL (REAR)

AWIIA0181GB

BLOWER MOTOR CONTROL SYSTEM

HAC-53

< COMPONENT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

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1.

Press the REAR CTRL switch (indicator on) on the rear air control (front) to send control of the rear blower
motor back the rear air control (rear).

2.

Turn the rear air control (rear) blower control dial to the lowest speed and check for rear blower operation.

3.

Continue checking that rear blower speed increases as the rear blower control dial is rotated clockwise.

Does the rear blower motor operate correctly?

YES

>> GO TO 4.

NO

>> Check rear air control (rear). Refer to

HAC-58, "Rear Air Control (Rear) Diagnosis Procedure #4"

.

4.

CHECK FOR SERVICE BULLETINS

Check for any service bulletins.

>> GO TO 5.

5.

RECHECK FOR ANY SYMPTOMS

Perform a complete operational check for any symptoms. Refer to

HAC-5, "Operational Check (Front)"

.

Does another symptom exist?

YES

>> Refer to

HAC-4, "How to Perform Trouble Diagnosis For Quick And Accurate Repair"

.

NO

>> INSPECTION END.

Rear Air Control (Front) Diagnosis Procedure #1

INFOID:0000000001366720

TROUBLE DIAGNOSIS PROCEDURE

1.

CHECK REAR AIR CONTROL (FRONT) POWER SUPPLY

1.

Disconnect rear air control (front) harness connector.

2.

Turn ignition switch ON.

3.

Check voltage between rear air control (front) harness connec-
tor R2 terminal 10 and ground.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Repair harness or connector.

2.

CHECK REAR AIR CONTROL (FRONT) FRONT AUX BLOWER POT REFERENCE VOLTAGE

1.

Disconnect rear air control (front) harness connector.

2.

Turn ignition switch ON.

3.

Check voltage between rear air control (front) harness connec-
tor R2 terminal 6 and ground.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> Repair harness or connector.

3.

CHECK REAR AIR CONTROL (FRONT) GROUND CIRCUIT

Battery voltage should exist.

AWIIA0253ZZ

Connector

Terminals

Voltage (Ap-

prox.)

(+)

(-)

Rear air control (front): R2

6

Ground

5V

AWIIA0252ZZ

HAC-54

< COMPONENT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

BLOWER MOTOR CONTROL SYSTEM

Check continuity between rear air control (front) harness connector
R2 terminal 1 and ground.

Is the inspection result normal?

YES

>> Replace A/C auto amp. Refer to

VTL-8, "Removal and

Installation"

.

NO

>> Repair harness or connector.

Rear Air Control (Rear) Diagnosis Procedure #2

INFOID:0000000001366721

TROUBLE DIAGNOSIS PROCEDURE

1.

CHECK REAR AIR CONTROL (FRONT) POWER SUPPLY

1.

Disconnect rear air control (front) harness connector.

2.

Turn ignition switch ON.

3.

Check voltage between rear air control (front) harness connec-
tor R2 terminal 10 and ground.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Repair harness or connector.

2.

CHECK REAR AIR CONTROL (FRONT) FRONT AUX BLOWER POT REFERENCE VOLTAGE

1.

Disconnect rear air control (front) harness connector.

2.

Turn ignition switch ON.

3.

Check voltage between rear air control (front) harness connec-
tor R2 terminal 6 and ground.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> GO TO 4.

3.

CHECK REAR AIR CONTROL (FRONT) GROUND CIRCUIT

1.

Turn ignition switch OFF.

2.

Check continuity between rear air control (front) harness con-
nector R2 terminal 1 and ground.

Is the inspection result normal?

YES

>> Replace rear air control (front).

NO

>> Repair harness or connector.

4.

CHECK REAR AIR CONTROL (FRONT) BLOWER POT CIRCUIT FOR OPEN

Continuity should exist.

AWIIA0254ZZ

Battery voltage should exist.

AWIIA0253ZZ

Connector

Terminals

Voltage (Ap-

prox.)

(+)

(-)

Rear air control (front): R2

6

Ground

5V

AWIIA0252ZZ

Continuity should exist.

AWIIA0254ZZ

BLOWER MOTOR CONTROL SYSTEM

HAC-55

< COMPONENT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

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HAC

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1.

Turn ignition switch OFF.

2.

Disconnect A/C auto amp. connector.

3.

Check continuity between A/C auto amp. harness connector
M50 (A) terminal 38 and rear air control (front) harness connec-
tor R2 (B) terminal 6.

Is the inspection result normal?

YES

>> Replace A/C auto amp. Refer to

VTL-8, "Removal and

Installation"

.

NO

>> Repair harness or connector.

Rear Air Control (Rear) Diagnosis Procedure #3

INFOID:0000000001430753

TROUBLE DIAGNOSIS PROCEDURE

1.

CHECK REAR AIR CONTROL (FRONT)

1.

Disconnect rear air control (front) connector.

2.

Turn ignition switch ON.

3.

Press AUTO switch.

Does rear blower motor operate in high speed?

YES

>> GO TO 17.

NO

>> GO TO 2.

2.

CHECK REAR BLOWER MOTOR POWER SUPPLY

1.

Turn ignition switch OFF.

2.

Disconnect rear blower motor harness connector.

3.

Turn ignition switch ON.

4.

Press AUTO switch.

5.

Rotate rear air control (front) blower speed control dial to maxi-
mum speed (REAR CTRL indicator off).

6.

Check voltage between rear blower motor harness connector
B201 terminal 2 and ground.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> GO TO 9.

3.

CHECK VARIABLE BLOWER CONTROL (REAR) POWER SUPPLY

1.

Turn ignition switch OFF.

2.

Disconnect variable blower control (rear) connector.

3.

Turn ignition switch ON.

4.

Check voltage between variable blower control connector B133
terminal 4 and ground.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Repair harness or connector.

4.

CHECK VARIABLE BLOWER CONTROL (REAR) AUX BLOWER SPEED SIGNAL CIRCUIT FOR SHORT

Continuity should exist.

AWIIA0244ZZ

Battery voltage should exist.

AWIIA0255ZZ

Battery voltage should exist.

AWIIA0245ZZ