Nissan Quest E52. Manual - part 749

HAC-126

< DTC/CIRCUIT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONING]

FRONT BLOWER MOTOR

NOTE:
Calculate drive signal duty ratio as shown in the figure.
T2 = Approx. 1.6 ms

Is the inspection result normal?

YES

>> Replace front blower motor. Refer to 

VTL-18, "FRONT BLOWER MOTOR : Removal and Installa-

tion"

.

NO

>> Replace front A/C control (A/C auto amp.). Refer to 

HAC-143, "Removal and Installation"

.

6.

CHECK FRONT BLOWER MOTOR POWER SUPPLY CIRCUIT FOR OPEN

1.

Turn ignition switch OFF. 

2.

Disconnect fuse block (J/B) connector. 

3.

Check continuity between fuse block (J/B) harness connector and front blower motor harness connector. 

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> Repair harness or connector.

7.

CHECK FRONT BLOWER RELAY GROUND CIRCUIT FOR OPEN

Check continuity between fuse block (J/B) harness connector and ground. 

Is the inspection result normal?

YES

>> GO TO 8.

NO

>> Repair harness or connector. 

8.

CHECK FRONT BLOWER RELAY

Check front blower relay. Refer to 

HAC-127, "Component Inspection (Front Blower Relay)"

.

Is the inspection result normal?

YES

>> Check front blower relay power supply circuit. Refer to 

PG-11, "Wiring Diagram - BATTERY

POWER SUPPLY -"

 and 

PG-54, "Wiring Diagram - IGNITION POWER SUPPLY -"

.

NO

>> Replace front blower relay.

Component Inspection (Front Blower Motor)

INFOID:0000000009652573

1.

CHECK FRONT BLOWER MOTOR-I

Front blower motor

Condition

Duty ratio

(Approx.)

Connector

Terminal

Fan speed (manual)

VENT mode

M140

2

1st

25 %

2nd

33 %

3rd

41 %

4th

51 %

5th

61 %

6th

69 %

7th

81 %

JPLIA1210GB

Fuse block (J/B)

Front blower motor

Continuity

Connector

Terminal

Connector

Terminal

M1

3A

M140

3

Existed

8A

Fuse block (J/B)

—

Continuity

Connector

Terminal

M3

7C

Ground

Existed

FRONT BLOWER MOTOR

HAC-127

< DTC/CIRCUIT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONING]

C

D

E

F

G

H

J

K

L

M

A

B

HAC

N

O

P

1.

Remove front blower motor. Refer to 

VTL-18, "FRONT BLOWER MOTOR : Removal and Installation"

.

2.

Check that there is not any mixing foreign object in the front blower motor. 

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Replace front blower motor. Refer to 

VTL-18, "FRONT BLOWER MOTOR : Removal and Installa-

tion"

.

2.

CHECK FRONT BLOWER MOTOR-II

Check that there is not breakage or damage in the front blower motor. 
Is the inspection result normal?

YES

>> GO TO 3.

NO

>> Replace front blower motor. Refer to 

VTL-18, "FRONT BLOWER MOTOR : Removal and Installa-

tion"

.

3.

CHECK FRONT BLOWER MOTOR-III

Check that front blower motor turns smoothly. 
Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Replace front blower motor. Refer to 

VTL-18, "FRONT BLOWER MOTOR : Removal and Installa-

tion"

.

Component Inspection (Front Blower Relay)

INFOID:0000000009652574

1.

CHECK FRONT BLOWER RELAY

1.

Remove front blower relay. Refer to 

PG-80, "Fuse, Connector and Terminal Arrangement"

.

2.

Check continuity between front blower relay terminal 3 and 5
when voltage is supplied between terminal 1 and 2. 

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Replace front blower relay.

Terminal

Voltage

Continuity

3

5

ON

Existed

OFF

Not existed

JSIIA1551ZZ

HAC-128

< DTC/CIRCUIT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONING]

REAR BLOWER MOTOR

REAR BLOWER MOTOR

Diagnosis Procedure

INFOID:0000000009652575

1.

CHECK FUSE

1.

Turn ignition switch OFF.

2.

Check 15A fuse (No. 23 and 24). 
NOTE:
Refer to 

PG-81, "Fuse and Fusible Link Arrangement"

. 

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Replace the blown fuse after repairing the affected circuit if a fuse is blown. 

2.

CHECK REAR BLOWER MOTOR POWER SUPPLY

1.

Disconnect rear blower motor connector.

2.

Turn ignition switch ON.

3.

Check voltage between rear blower motor harness connector and ground. 

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> GO TO 6.

3.

CHECK REAR BLOWER MOTOR GROUND CIRCUIT FOR OPEN

1.

Turn ignition switch OFF.

2.

Check continuity between rear blower motor harness connector and ground. 

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Repair harness or connector. 

4.

CHECK REAR BLOWER MOTOR CONTROL SIGNAL CIRCUIT FOR OPEN

1.

Disconnect A/C auto amp. connector. 

2.

Check continuity between rear blower motor harness connector and A/C auto amp. harness connector. 

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Repair harness or connector.

5.

CHECK REAR BLOWER MOTOR CONTROL SIGNAL

1.

Reconnect rear blower motor connector and A/C auto amp. connector. 

2.

Turn ignition switch ON.

3.

Operate MODE switch (front A/C control) to set air outlet of rear air conditioning to VENT.

4.

Change rear fan speed from Lo to Hi, and check duty ratios between rear blower motor harness connector
and ground by using an oscilloscope. 

+

−

Voltage

Rear blower motor

Connector

Terminal

B403

3

Ground

11 – 14 V

Rear blower motor

—

Continuity

Connector

Terminal

B403

1

Ground

Existed

Rear blower motor

A/C auto amp.

Continuity

Connector

Terminal

Connector

Terminal

B403

2

M50

30

Existed

REAR BLOWER MOTOR

HAC-129

< DTC/CIRCUIT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONING]

C

D

E

F

G

H

J

K

L

M

A

B

HAC

N

O

P

NOTE:
Calculate drive signal duty ratio as shown in the figure.
T2 = Approx. 1.6 ms

Is the inspection result normal?

YES

>> Replace rear blower motor. Refer to 

VTL-18, "REAR BLOWER MOTOR : Removal and Installa-

tion"

.

NO

>> Replace front A/C control (A/C auto amp.). Refer to 

HAC-143, "Removal and Installation"

.

6.

CHECK REAR BLOWER MOTOR POWER SUPPLY CIRCUIT FOR OPEN

1.

Turn ignition switch OFF. 

2.

Disconnect rear blower relay connector. 

3.

Check continuity between rear blower relay harness connector and rear blower motor harness connector. 

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> Repair harness or connector.

7.

CHECK REAR BLOWER RELAY GROUND CIRCUIT FOR OPEN

Check continuity between rear blower relay harness connector and ground. 

Is the inspection result normal?

YES

>> GO TO 8.

NO

>> Repair harness or connector. 

8.

CHECK REAR BLOWER RELAY

Check rear blower relay. Refer to 

HAC-130, "Component Inspection (Rear Blower Relay)"

.

Is the inspection result normal?

YES

>> Check rear blower relay power supply circuit. Refer to 

PG-11, "Wiring Diagram - BATTERY

POWER SUPPLY -"

 and 

PG-54, "Wiring Diagram - IGNITION POWER SUPPLY -"

.

NO

>> Replace rear blower relay.

Component Inspection (Rear Blower Motor)

INFOID:0000000009652576

1.

CHECK REAR BLOWER MOTOR-I

Rear blower motor

Condition

Duty ratio

(Approx.)

Connector

Terminal

Fan speed (manual)

VENT mode

B403

2

1st

25 %

2nd

33 %

3rd

41 %

4th

51 %

5th

61 %

6th

69 %

7th

81 %

JPLIA1210GB

Rear blower relay

Rear blower motor

Continuity

Connector

Terminal

Connector

Terminal

M14

5

B403

3

Existed

7

Rear blower relay

—

Continuity

Connector

Terminal

M14

2

Ground

Existed