Nissan Frontier. Manual - part 867

HAC-22

< DTC/CIRCUIT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

MODE DOOR MOTOR

The mode door motor is attached to the heater & cooling unit assem-

bly. It rotates so that air is discharged from the outlet as indicated by

the front air control. Motor rotation is conveyed to a link which acti-

vates the mode door.

Mode Door Motor Component Function Check

INFOID:0000000009478275

INSPECTION FLOW

1.

CONFIRM SYMPTOM BY PERFORMING OPERATIONAL CHECK - DISCHARGE AIR

1. Press each mode switch and press the 

 (DEF) switch. Each position indicator should illuminate.

2. Confirm that discharge air comes out according to the air distribution table. Refer to 

HAC-15, "Discharge

Air Flow"

.

NOTE:

Confirm that the compressor clutch is engaged (visual inspection) and intake door position is at FRESH

 when DEF (

) or D/F (

) is selected.

Is the inspection result normal?

YES

>> Inspection End.

NO

>> Go to diagnosis procedure. Refer to 

HAC-22, "Mode Door Motor Diagnosis Procedure"

.

Mode Door Motor Diagnosis Procedure

INFOID:0000000009478276

Regarding Wiring Diagram information, refer to 

HAC-63, "Wiring Diagram - Automatic Air Conditioner"

.

SYMPTOM:

• Air outlet does not change.

• Mode door motor does not operate normally.

1.

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

1. Turn ignition switch ON.

2. Using CONSULT, check "MODE FDBCK" in "DATA MONITOR" mode in "HVAC". Refer to 

HAC-17, "CON-

SULT Function (HVAC)"

.

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

Is the inspection result normal?

YES

>> • Mode door motor is OK.

• Inspect mode door for mechanical failure. Refer to 

VTL-21, "Removal and Installation"

.

NO

>> GO TO 2.

2.

CHECK MODE DOOR MOTOR CIRCUITS FOR OPEN AND SHORT TO GROUND 

1. Turn ignition switch OFF.

2. Disconnect the front air control harness connector M52 and the mode door motor harness connector

M142.

3. Check continuity between front air control harness connector M52 terminals 19, 20 and the mode door

motor harness connector M142 terminals 6, 1.

WJIA1484E

Monitor Item

Condition

Results

MODE FDBCK

Cycle mode switch through all modes, D/F 

(

),  VENT  (

),  B/L  (

),  and  FOOT(

)

Voltage varies between D/F (

) and VENT (

), and 

between VENT (

) and B/L (

).

MODE DOOR MOTOR

HAC-23

< DTC/CIRCUIT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

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HAC

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4. Check continuity between front air control harness connector

M52 terminals 19, 20 and ground.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> Repair or replace harness as necessary.

3.

CHECK FRONT AIR CONTROL FOR MODE DOOR MOTOR POWER AND GROUND 

1. Reconnect front air control harness connector.

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

) mode. 

4. Check voltage between front air control harness connector M52

terminal 19 and terminal 20 while pressing the mode switch to
the VENT (

), and then the B/L (

) mode. 

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Replace front air control. Refer to 

VTL-7, "Removal and Installation"

.

4.

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

1. Turn ignition switch OFF.

2. Disconnect the front air control harness connectors.

3. Check continuity between front air control harness connector M52 terminal 3, and M56 terminal 28 and

the mode door motor harness connector M142 terminals 2, 3.

4. Check continuity between front air control harness connector M52 terminal 3, M56 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

Connector

Terminal

Continuity

M52

19

M142

6

Yes

20

1

Connector

Terminal

—

Continuity

M52

19

Ground

No

20

AWIIA0361ZZ

Connector

Terminals

Condition Voltage 

(Approx.)

(+) (-)

M52

19

20

D/F (

) mode to VENT (

) mode

Battery voltage

20

19

VENT (

) mode to B/L (

) mode

Battery voltage

AWIIA0360ZZ

Connector

Terminal

Connector

Terminal

Continuity

M52

3

M142

2

Yes

M56

28

3

Connector

Terminal

—

Continuity

M52

3

Ground

No

M56

28

HAC-24

< DTC/CIRCUIT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

MODE DOOR MOTOR

1. Check continuity between front air control harness connector M52 terminal 7 and mode door motor har-

ness connector M142 terminal 4.

2. Check continuity between front air control harness connector

M52 terminal 7 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 M52

(B) terminal 3, and M56 (A) terminal 28.

4. Check voltage between front air control harness connector M52

terminal 7 and ground.

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> Replace front air control. Refer to 

VTL-7, "Removal and

Installation"

.

7.

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 M52

terminal 7 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

Terminal

Connector

Terminal

Continuity

M52

7

M142

4

Yes

Connector

Terminal

—

Continuity

M52

7

Ground

No

AWIIA0370ZZ

A

B

Connector

Terminals

Connector

Terminals

Voltage (Approx.)

(+)

(-) 

M56

28

M52

3

5 Volts

Connector

Terminal

—

Voltage (Approx.)

M52

7

Ground

0 Volts

AWIIA0813ZZ

AWIIA0369ZZ

Connector

Terminal

—

Voltage (Approx.)

M52

7

Ground

0.2 to 4.8 Volts

AWIIA0369ZZ

AIR MIX DOOR MOTOR

HAC-25

< DTC/CIRCUIT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

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AIR MIX DOOR MOTOR

System Description

INFOID:0000000009478277

SYSTEM DESCRIPTION

SYMPTOM:

• Discharge air temperature does not change.

• Air mix door motor does not operate.

SYSTEM DESCRIPTION

Component Parts

Air mix door control system components are:

• Front air control

• Air mix door motors (driver, passenger)

• PBR (built-into air mix door motors)

• In-vehicle sensor

• Ambient sensor

• Optical sensor

• Intake sensor

System Operation

The front air control receives data from the temperature selected by the driver side, passenger side, and rear.

The front air control then applies a voltage to one circuit of the appropriate air mix door motor, while ground is

applied to the other circuit, causing the appropriate 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 con-

trol monitors the air mix door positions by measuring the voltage signal on the PBR circuits of each door.

In AUTO mode the air mix, intake, mode door, and defrost door positions are set by the front air control which

determines the proper position based on inputs from the in-vehicle sensor, ambient sensor, optical sensor,

intake sensor, and the temperature selected by the driver and front and rear passengers.

Subsequently, HOT/COLD or DEFROST/VENT or FRESH/RECIRCULATION operation is selected. The new

door position data is returned to the front air control

AWIIA0372GB