Nissan Sentra. Manual - part 557

HAC-76

< DTC/CIRCUIT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

B27AA, B27AB, B27AC, B27AD AIR MIX DOOR MOTOR (PASSENGER SIDE)

NO

>> Replace air mix door motor RH. Refer to 

HAC-112, "AIR MIX DOOR MOTOR : Removal and

Installation - Air Mix Door Motor RH"

.

B27A6, B27A7, B27A8, B27A9 MODE DOOR MOTOR

HAC-77

< DTC/CIRCUIT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

C

D

E

F

G

H

J

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M

A

B

HAC

N

O

P

B27A6, B27A7, B27A8, B27A9 MODE DOOR MOTOR

DTC Logic

INFOID:0000000009757672

DTC DETECTION LOGIC 

NOTE:

• If DTC is displayed along with DTC U1000, first perform the trouble diagnosis for DTC U1000. Refer to 

HAC-

58, "DTC Logic"

.

• If DTC is displayed along with DTC U1010, first perform the trouble diagnosis for DTC U1010. Refer to 

HAC-

59, "DTC Logic"

.

• If mode door motors DTC (B27A6 – B27A9) are detected, there is probably a disconnected connector or an

open circuit in mode door motor drive power supply harness.

DTC CONFIRMATION PROCEDURE

1.

PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT

1. Turn ignition switch ON.

2. Select “Self Diagnostic Result” mode of “HVAC” using CONSULT.

3. Check DTC.
Is DTC detected?

YES

>> Refer to 

HAC-77, "Diagnosis Procedure"

.

NO

>> Inspection End.

Diagnosis Procedure

INFOID:0000000009757673

Regarding Wiring Diagram information, refer to 

HAC-41, "Wiring Diagram"

.

1.

CHECK MODE DOOR MOTOR POWER SUPPLY

1. Turn ignition switch OFF.

2. Disconnect mode door motor connector.

3. Turn ignition switch ON.

4. Check voltage between mode door motor harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Repair harness or connector between mode door motor and fuse.

2.

CHECK MODE DOOR MOTOR DRIVE SIGNAL CIRCUIT FOR OPEN

DTC

Items

(CONSULT screen terms)

DTC detection condition

Possible cause

B27A6

MODE DOOR MOTOR

Short or open circuit of mode door motor drive 
signal terminal 1.

• Mode door motor
• A/C auto amp.
• Harness or connectors

(The motor circuit is open or short-
ed.)

B27A7

Short or open circuit of mode door motor drive 
signal terminal 2.

B27A8

Short or open circuit of mode door motor drive 
signal terminal 3.

B27A9

Short or open circuit of mode door motor drive 
signal terminal 4.

+

−

Voltage

Mode door motor

Connector

Terminal

M126

5

Ground

Battery voltage

HAC-78

< DTC/CIRCUIT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

B27A6, B27A7, B27A8, B27A9 MODE DOOR MOTOR

1. Turn ignition switch OFF.

2. Disconnect A/C auto amp. connector.

3. Check continuity between mode door motor harness connector and A/C auto amp. harness connector.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> Repair harness or connector.

3.

CHECK MODE DOOR MOTOR DRIVE SIGNAL CIRCUIT FOR SHORT

Check continuity between mode door motor harness connector and A/C auto amp. harness connector.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Repair harness or connector.

4.

CHECK MODE DOOR MOTOR

Check mode door motor. Refer to 

HAC-78, "Component Inspection"

.

Is the inspection result normal?

YES

>> Replace A/C auto amp. Refer to 

HAC-105, "Removal and Installation"

.

NO

>> Replace mode door motor. Refer to 

HAC-112, "MODE DOOR MOTOR : Removal and Installa-

tion"

.

Component Inspection

INFOID:0000000009757674

1.

CHECK MODE DOOR MOTOR

1. Remove mode door motor. Refer to 

HAC-112, "MODE DOOR MOTOR : Removal and Installation"

.

2. Check resistance between mode door motor terminals. Refer to applicable table for the normal value. 

Is the inspection result normal?

YES

>> Inspection End.

NO

>> Replace mode door motor. Refer to 

HAC-112, "MODE DOOR MOTOR : Removal and Installa-

tion"

.

Mode door motor

A/C auto amp.

Continuity

Connector

Terminal

Connector

Terminal

M126

4

M34

37

Yes

3

38

2

39

1

40

Mode door motor

—

Continuity

Connector

Terminal

M126

4

Ground

No

3

2

1

Terminal

Resistance (

Ω)

(Approx.)

5

1

90

2

3

4

B27A0, B27A1 INTAKE DOOR MOTOR

HAC-79

< DTC/CIRCUIT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

C

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HAC

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B27A0, B27A1 INTAKE DOOR MOTOR 

DTC Logic

INFOID:0000000009757675

DTC DETECTION LOGIC 

NOTE:

• If DTC is displayed along with DTC U1000, first perform the trouble diagnosis for DTC U1000. Refer to 

HAC-

58, "DTC Logic"

.

• If DTC is displayed along with DTC U1010, first perform the trouble diagnosis for DTC U1010. Refer to 

HAC-

59, "DTC Logic"

.

*: A/C auto amp. operates intake door motor according to target value of PBR opening angle at 40% when per-

forming self-diagnosis.

DTC CONFIRMATION PROCEDURE

1.

PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT

1. Start engine.

2. Select “Self Diagnostic Result” mode of “HVAC” using CONSULT.

3. Check DTC.
Is DTC detected?

YES

>> Refer to 

HAC-79, "Diagnosis Procedure"

.

NO

>> Inspection End.

Diagnosis Procedure

INFOID:0000000009757676

Regarding Wiring Diagram information, refer to 

HAC-41, "Wiring Diagram"

.

1.

CHECK INTAKE DOOR MOTOR OPERATION

1. Turn ignition switch ON.

2. Operate intake switch and check by operation sound that intake door motor operates.
Does the intake door motor operate?

YES

>> GO TO 2.

NO

>> GO TO 8.

2.

CHECK INTAKE DOOR MOTOR PBR POWER SUPPLY

1. Disconnect intake door motor connector.

2. Turn ignition switch ON.

3. Check voltage between intake door motor harness connector and ground.

Is the inspection result normal?

DTC

Items

(CONSULT screen terms)

DTC detection condition

*

Possible cause

B27A0

INTAKE DOOR MOTOR

PBR opening angle of intake door motor is 50% 
or more. (PBR feedback signal voltage of intake 
door motor is 2.5 V or more)

• Intake door motor
• Intake door motor system installa-

tion condition

• A/C auto amp.
• Harness or connectors

(The motor circuit is open or short-
ed.)

B27A1

PBR opening angle of intake door motor is 30% 
or less. (PBR feedback signal voltage of intake 
door motor is 1.5 V or less)

+

−

Voltage

(Approx.)

Intake door motor

Connector

Terminal

M58

1

Ground

5 V