Nissan Titan A60. Manual - part 589

DEFROSTER DOOR MOTOR CIRCUIT

HAC-39

< DTC/CIRCUIT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

C

D

E

F

G

H

J

K

L

M

A

B

HAC

N

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P

1.

CONFIRM SYMPTOM BY PERFORMING OPERATIONAL CHECK - DEFROSTER DOOR

1. Select vent (

) mode.

2. Press the defrost switch (

). Defroster indicator should illuminate. 

3. Listen for defroster door position change (blower sound should change slightly).
Is the inspection result normal?

YES

>> Inspection End.

NO

>> Go to diagnosis procedure. Refer to 

HAC-39, "Defroster Door Motor Diagnosis Procedure"

.

Defroster Door Motor Diagnosis Procedure

INFOID:0000000006708578

Regarding Wiring Diagram information, refer to 

HAC-71, "Wiring Diagram - Automatic Air Conditioner"

.

SYMPTOM:

• Defroster door does not change.

• Defroster door motor does not operate normally.

1.

CHECK DEFROSTER DOOR MOTOR POSITION BALANCED RESISTOR (PBR) FEEDBACK VOLTAGE

1. Turn ignition switch ON.

2. Using CONSULT-III, check "DEF FDBCK" in "DATA MONITOR" mode in "HVAC". Refer to 

HAC-17,

"CONSULT-III Function (HVAC)"

.

3. Observe "DEF FDBCK" voltage while cycling front air control mode switch through all modes and pressing

DEF switch.

Is the inspection result normal?

YES

>> • Defroster door motor is OK.

• Inspect defroster door for mechanical failure. Refer to 

VTL-17, "Removal and Installation"

.

NO

>> GO TO 2.

2.

CHECK DEFROSTER DOOR MOTOR CIRCUITS FOR OPEN AND SHORT TO GROUND 

1. Turn ignition switch OFF.

2. Disconnect the front air control harness connector M49 (A) and

the defroster door motor harness connector M144 (B).

3. Check continuity between front air control harness connector

M49 (A) terminals 23, 24 and the defroster door motor harness

connector M144 (B) terminals 1, 6.

Monitor Item

Condition

Results

DEF FDBCK

Cycle mode switch through all modes, D/F 

(

), VENT (

), B/L (

), FOOT(

), and 

press DEF (

)

Voltage varies between 0.2 and 4.8 volts.

A

B

Continuity

Connector

Terminal

Connector

Terminal

M49

23

M144

1

Yes

24

6

AWIIA0406ZZ

HAC-40

< DTC/CIRCUIT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

DEFROSTER DOOR MOTOR CIRCUIT

4. Check continuity between front air control harness connector

M49 terminals 23, 24 and ground.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> Repair or replace harness as necessary.

3.

CHECK FRONT AIR CONTROL FOR DEFROSTER DOOR MOTOR POWER AND GROUND 

1. Reconnect front air control harness connector.

2. Turn ignition switch ON.
3. Press the mode switch to the VENT (

) mode. 

4. Check voltage between front air control harness connector M49

terminal 23 and terminal 24 while pressing the defroster switch
(

). 

Is the inspection result normal?

YES

>> GO TO 4.

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 M49 (C) and

M50 (A).

3. Check continuity between front air control harness connector

M49 (C) terminal 3, and M50 (A) terminal 28 and the defroster

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

4. Check continuity between front air control harness connector M49 (C) terminal 3, M50 (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 

Connector

Terminal

—

Continuity

M49

23

Ground

No

24

AWIIA0403ZZ

Connector

Terminals

Condition Voltage 

(Approx.)

(+) (-)

M49

23

24

Following defroster switch (

) on

Battery voltage

24

23

Following defroster switch (

) off

Battery voltage

AWIIA0404ZZ

A and C

B

Continuity

Connector

Terminal

Connector

Terminal

M49 (C)

3

M144

2

Yes

M50 (A)

28

3

Connector

Terminal

—

Continuity

M49 (C)

3

Ground

No

M50 (A)

28

AWIIA0393ZZ

DEFROSTER DOOR MOTOR CIRCUIT

HAC-41

< DTC/CIRCUIT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

C

D

E

F

G

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A

B

HAC

N

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1. Check continuity between front air control harness connector

M49 (A) terminal 10 and defroster door motor harness connec-

tor M144 (B) terminal 4.

2. Check continuity between front air control harness connector

M49 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 

1. Reconnect front air control harness connectors.

2. Turn ignition switch ON.

3. Check voltage between front air control harness connector M49

(B) terminal 3, and M50 (A) terminal 28.

4. Check voltage between front air control harness connector M49

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 

A

B

Continuity

Connector

Terminal

Connector

Terminal

M49

10

M144

4

Yes

AWIIA0410ZZ

Connector

Terminal

—

Continuity

M49

10

Ground

No

AWIIA0409ZZ

A

B

Connector

Terminals

Connector

Terminals

Voltage (Approx.)

(+)

(-) 

M50

28

M49

3

5 Volts

AWIIA0407ZZ

Connector

Terminal

—

Voltage (Approx.)

M49

10

Ground

0 Volts

AWIIA0408ZZ

HAC-42

< DTC/CIRCUIT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

DEFROSTER DOOR MOTOR CIRCUIT

1. Reconnect the defroster door motor harness connector M144.

2. Check voltage between front air control harness connector M49

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"

.

Connector

Terminal

—

Voltage (Approx.)

M49

10

Ground

0.2 to 4.8 Volts

AWIIA0408ZZ