Nissan Titan. Manual - part 406

DEFROSTER DOOR MOTOR CIRCUIT

HAC-129

< DTC/CIRCUIT DIAGNOSIS >

[MANUAL A/C (TYPE 1)]

C

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F

G

H

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A

B

HAC

N

O

P

NO

>> Replace front air control. Refer to 

VTL-8, "Removal and Installation"

.

4.

CHECK DEFROSTER DOOR MOTOR PBR CIRCUITS FOR OPEN AND SHORT TO GROUND 

1. Turn ignition switch OFF.

2. Disconnect the front air control harness connectors M180 (C)

and M181 (A).

3. Check continuity between front air control harness connector

M180 (C) terminal 3, and M181 (A) terminal 28 and the defroster

door motor harness connector M144 (B) terminals 2, 3.

4. Check continuity between front air control harness connector M180 (C) terminal 3, M181 (A) terminal 28

and ground.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Repair or replace harness as necessary.

5.

CHECK PBR FEEDBACK SIGNAL CIRCUIT FOR OPEN AND SHORT TO GROUND 

1. Check continuity between front air control harness connector

M180 (A) terminal 10 and defroster door motor harness connec-

tor M144 (B) terminal 4.

2. Check continuity between front air control harness connector

M180 terminal 10 and ground.

Is the inspection result normal?

YES

>> GO TO 6.

NO

>> Repair or replace harness as necessary.

6.

CHECK FRONT AIR CONTROL FOR 5 VOLT REFERENCE (VREF), VREF RETURN, AND FEEDBACK

SIGNAL 

A and C

B

Continuity

Connector

Terminal

Connector

Terminal

M180 (C)

3

M144

2

Yes

M181 (A)

28

3

Connector

Terminal

—

Continuity

M180 (C)

3

Ground

No

M181 (A)

28

AWIIA0393ZZ

A

B

Continuity

Connector

Terminal

Connector

Terminal

M180

10

M144

4

Yes

AWIIA0410ZZ

Connector

Terminal

—

Continuity

M180

10

Ground

No

AWIIA0409ZZ

HAC-130

< DTC/CIRCUIT DIAGNOSIS >

[MANUAL A/C (TYPE 1)]

DEFROSTER DOOR MOTOR CIRCUIT

1. Reconnect front air control harness connectors.

2. Turn ignition switch ON.

3. Check voltage between front air control harness connector

M180   (B) terminal 3, and M181 (A) terminal 28.

4. Check voltage between front air control harness connector

M180 terminal 10 and ground.

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> Replace front air control. Refer to 

VTL-8, "Removal and

Installation"

.

7.

CHECK FRONT AIR CONTROL FOR FEEDBACK SIGNAL 

1. Reconnect the defroster door motor harness connector M144.

2. Check voltage between front air control harness connector

M180 terminal 10 and ground.

Is the inspection result normal?

YES

>> Inspect defroster door for binding or mechanical failure.

If defroster door moves freely, replace front air control.

Refer to 

VTL-8, "Removal and Installation"

.

NO

>> Replace the defroster door motor. Refer to 

VTL-17,

"Removal and Installation"

.

A

B

Connector

Terminals

Connector

Terminals

Voltage (Approx.)

(+)

(-) 

M181

28

M180

3

5 Volts

AWIIA0407ZZ

Connector

Terminal

—

Voltage (Approx.)

M180

10

Ground

0 Volts

AWIIA0408ZZ

Connector

Terminal

—

Voltage (Approx.)

M180

10

Ground

0.2 to 4.8 Volts

AWIIA0408ZZ

BLOWER MOTOR CONTROL SYSTEM

HAC-131

< DTC/CIRCUIT DIAGNOSIS >

[MANUAL A/C (TYPE 1)]

C

D

E

F

G

H

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A

B

HAC

N

O

P

BLOWER MOTOR CONTROL SYSTEM

System Description

INFOID:0000000009882528

SYSTEM DESCRIPTION

Component Parts

Blower speed control system components are:

• Front air control

• Variable blower control

• Front blower motor relay

• Front blower motor

• Ambient sensor

• Intake sensor

System Operation

COMPONENT DESCRIPTION

Variable Blower Control

The variable blower control is located on the cooling unit. The vari-

able blower control receives a gate voltage from the front air control

to steplessly maintain the blower motor voltage in the 0 to 5 volt

range (approx.).

Front Blower Motor Component Function Check

INFOID:0000000009882529

INSPECTION FLOW

1.

CONFIRM SYMPTOM BY PERFORMING OPERATIONAL CHECK - FRONT BLOWER

1. Rotate the blower control dial clockwise once. Blower motor should operate in low speed.

2. Rotate the blower control dial clockwise, and continue checking blower speed until all speeds are

checked.

Is the inspection result normal?

YES

>> Inspection End.

WJIA1385E

WJIA0559E

HAC-132

< DTC/CIRCUIT DIAGNOSIS >

[MANUAL A/C (TYPE 1)]

BLOWER MOTOR CONTROL SYSTEM

NO

>> Go to diagnosis procedure. Refer to 

HAC-132, "Front Blower Motor Diagnosis Procedure"

.

Front Blower Motor Diagnosis Procedure

INFOID:0000000009882530

Regarding Wiring Diagram information, refer to 

HAC-155, "Wiring Diagram - Manual With 2 Control Dial Sys-

tem"

.

SYMPTOM: Blower motor operation is malfunctioning.

DIAGNOSTIC PROCEDURE FOR BLOWER MOTOR

SYMPTOM: Blower motor operation is malfunctioning under starting

blower speed control.

1.

CHECK FUSES

Check 20A fuses [No. 24 and 27 (Located in the fuse and fusible link box)]. For fuse layout. Refer to 

PG-76,

"Terminal Arrangement"

.

Is the inspection result normal?

YES

>> GO TO 2.

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. Rotate blower control dial 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 11.

NO

>> GO TO 3.

3.

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

AWIIA1115GB

Fuses are good.

2 - Ground

: Battery voltage

WJIA1331E