Nissan Titan. Instruction — part 426

DEFROSTER DOOR MOTOR CIRCUIT

HAC-209

< DTC/CIRCUIT DIAGNOSIS >

[MANUAL A/C (TYPE 2)]

C

D

E

F

G

H

J

K

L

M

A

B

HAC

N

O

P

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Repair or replace harness as necessary.

4.

CHECK PBR FEEDBACK SIGNAL CIRCUIT FOR OPEN AND SHORT TO GROUND

1. Check continuity between front air control harness connector

M176 (A) terminal 25 and defroster door motor harness connec-

tor M144 (B) terminal 4.

2. Check continuity between front air control harness connector

M176 terminal 25 and ground.

Is the inspection result normal?

YES

>> GO TO 6.

NO

>> Repair or replace harness as necessary.

5.

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

M176 terminals 2, 15.

Connector

Terminal

—

Continuity

M176

2

Ground

No

15

A

B

Continuity

Connector

Terminal

Connector

Terminal

M176

25

M144

4

Yes

AWIIA0534ZZ

Connector

Terminal

—

Continuity

M176

25

Ground

No

AWIIA0533ZZ

Connector

Terminals

Connector

Terminals

Voltage (Approx.)

(+)

(-)

M176

2

M176

15

5 Volts

AWIIA0494ZZ

HAC-210

< DTC/CIRCUIT DIAGNOSIS >

[MANUAL A/C (TYPE 2)]

DEFROSTER DOOR MOTOR CIRCUIT

4. Check voltage between front air control harness connector

M176 terminal 25 and ground.

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> Replace front air control. Refer to

VTL-8, "Removal and

Installation"

.

6.

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

M176 terminal 25 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.)

M176

25

Ground

0 Volts

AWIIA0532ZZ

Connector

Terminal

—

Voltage (Approx.)

M176

25

Ground

0.2 to 4.8 Volts

AWIIA0532ZZ

BLOWER MOTOR CONTROL SYSTEM

HAC-211

< DTC/CIRCUIT DIAGNOSIS >

[MANUAL A/C (TYPE 2)]

C

D

E

F

G

H

J

K

L

M

A

B

HAC

N

O

P

BLOWER MOTOR CONTROL SYSTEM

System Description

INFOID:0000000009882587

SYSTEM DESCRIPTION

Component Parts

Blower speed control system components are:

• Front air control

• Variable blower control

• Front blower motor relay

• Front blower motor

• Intake sensor

System Operation

COMPONENT DESCRIPTION

Variable Blower Control

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

able blower control (1) receives a gate voltage from the front air con-

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

range (approx.).

Front Blower Motor Component Function Check

INFOID:0000000009882588

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.

NO

>> Go to diagnosis procedure. Refer to

HAC-212, "Front Blower Motor Diagnosis Procedure"

WJIA1385E

AWIIA1082ZZ

HAC-212

< DTC/CIRCUIT DIAGNOSIS >

[MANUAL A/C (TYPE 2)]

BLOWER MOTOR CONTROL SYSTEM

Front Blower Motor Diagnosis Procedure

INFOID:0000000009882589

Regarding Wiring Diagram information, refer to

HAC-232, "Wiring Diagram - Instruction With 3 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

AWIIA0535GB

Fuses are good.

2 - Ground

: Battery voltage

WJIA1331E