Nissan Frontier. Manual - part 888

HAC-106

< DTC/CIRCUIT DIAGNOSIS >

[MANUAL A/C (TYPE 1)]

MODE DOOR MOTOR

4. Check voltage between front air control harness connector M50 terminal 10 and ground.

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> Replace front air control. Refer to 

VTL-7, "Removal and Installation"

.

6.

CHECK FRONT AIR CONTROL FOR FEEDBACK SIGNAL 

1. Reconnect the mode door motor harness connector M142.

2. Check voltage between front air control harness connector M50 terminal 10 and ground.

Is the inspection result normal?

YES

>> Inspect mode door for binding or mechanical failure. If mode door moves freely, replace front air

control. Refer to 

VTL-7, "Removal and Installation"

.

NO

>> Replace the mode door motor. Refer to 

VTL-21, "Removal and Installation"

.

Connector

Terminals

Connector

Terminals

Voltage (Approx.)

(+)

(-) 

M59

28

M50

3

5 Volts

Connector

Terminal

—

Voltage (Approx.)

M50

10

Ground

0 Volts

Connector

Terminal

—

Voltage (Approx.)

M50

10

Ground

0.2 to 4.8 Volts

AIR MIX DOOR MOTOR

HAC-107

< DTC/CIRCUIT DIAGNOSIS >

[MANUAL A/C (TYPE 1)]

C

D

E

F

G

H

J

K

L

M

A

B

HAC

N

O

P

AIR MIX DOOR MOTOR

System Description

INFOID:0000000009478338

SYSTEM DESCRIPTION

Component Parts

Air mix door control system components are:

• Front air control

• Air mix door motor 

• Position Balanced Resistor (PBR) (built into air mix door motor)

• Intake sensor

System Operation

The front air control receives data from the temperature selected by the driver. The front air control then

applies a voltage to one circuit of the air mix door motor, while ground is applied to the other circuit, causing

the air mix door motor to rotate. The direction of rotation is determined by which circuit has voltage applied to

it, and which one has ground applied to it. The front air control monitors the air mix door positions by measur-

ing the voltage signal on the PBR circuits of each door.

Air Mix Door Control Specification

COMPONENT DESCRIPTION

Air Mix Door Motor

WJIA1316E

WJIA0435E

HAC-108

< DTC/CIRCUIT DIAGNOSIS >

[MANUAL A/C (TYPE 1)]

AIR MIX DOOR MOTOR

The air mix door motor is attached to the heater and cooling unit

assembly. This motor rotates so that the air mix door is opened or

closed to a position set by the front air control. Motor rotation is then

conveyed through a shaft and the air mix door position is then fed

back to the front air control by the PBR built into the air mix door

motor.

Air Mix Door Motor Component Function Check

INFOID:0000000009478339

INSPECTION FLOW

1.

CONFIRM SYMPTOM BY PERFORMING OPERATIONAL CHECK - TEMPERATURE INCREASE

1. Blower must be ON.

2. Turn the temperature control dial clockwise to maximum heat.

3. Check for hot air at discharge air outlets.

>> GO TO 2.

2.

CONFIRM SYMPTOM BY PERFORMING OPERATIONAL CHECK - TEMPERATURE DECREASE

1. Turn the temperature control dial counterclockwise to maximum cold.

2. Check for cold air at discharge air outlets.
Is the inspection result normal?

YES

>> Inspection End.

NO

>> Go to diagnosis procedure. Refer to 

HAC-108, "Air Mix Door Motor Diagnosis Procedure"

.

Air Mix Door Motor Diagnosis Procedure

INFOID:0000000009478340

Regarding Wiring Diagram information, refer to 

HAC-133, "Wiring Diagram - With Type 1"

.

SYMPTOM:

• Discharge air temperature does not change.

• Air mix door motor does not operate normally.

1.

CHECK AIR MIX DOOR MOTOR CIRCUITS FOR OPEN AND SHORT TO GROUND 

1. Turn ignition switch OFF.

2. Disconnect the front air control harness connector M50 (A) and

the air mix door motor harness connector M147 (B).

3. Check continuity between front air control harness connector

M50 (A) terminals 17, 18 and the air mix door motor harness

connector M147 (B) terminals 5, 6.

WJIA1636E

A

B

Continuity

Connector

Terminal

Connector

Terminal

M50

18

M147

6

Yes

17

5

AWIIA1206ZZ

AIR MIX DOOR MOTOR

HAC-109

< DTC/CIRCUIT DIAGNOSIS >

[MANUAL A/C (TYPE 1)]

C

D

E

F

G

H

J

K

L

M

A

B

HAC

N

O

P

4. Check continuity between front air control harness connector

M50 terminals 17, 18 and ground.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> Repair or replace harness as necessary.

2.

CHECK FRONT AIR CONTROL FOR AIR MIX DOOR MOTOR POWER AND GROUND 

1. Reconnect front air control harness connector.

2. Turn ignition switch ON.
3. Press the mode switch D/F (

) mode. 

4. Check voltage between front air control harness connector M50

terminal 17 and terminal 18 while pressing the mode switch to
VENT (

), and then to B/L (

) mode. 

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Replace front air control. Refer to 

VTL-7, "Removal and Installation"

.

3.

CHECK AIR MIX DOOR MOTOR PBR CIRCUITS FOR OPEN AND SHORT TO GROUND 

1. Turn ignition switch OFF.

2. Disconnect the front air control harness connector M50.

3. Check continuity between front air control harness connector M50 (A) terminal 3 and M59 (A) terminal 28,

and the air mix door motor harness connector M147 (B) terminals 1, 3.

4. Check continuity between front air control harness connector M50 (A) terminal 3 and M59 (A) terminal 28,

and ground.

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 

Connector

Terminal

—

Continuity

M50

17

Ground

No

18

AWIIA0374ZZ

Connector

Terminals

Condition Voltage 

(Approx.)

(+) (-)

M50

18

17

Pressing the mode switch from D/F 

(

) mode to VENT (

) mode

Battery voltage

17

18

Pressing the mode switch from VENT 

(

)  mode  to  B/L  (

)  mode

Battery voltage

AWIIA0373ZZ

A

B

Continuity

Connector

Terminal

Connector

Terminal

M50

3

M147

3

Yes

M59

28

1

Connector

Terminal

—

Continuity

M50 (A)

3

Ground

No

M59 (A)

28