Nissan Leaf. Manual - part 777

B27A2, B27A3, B27A4, B27A5 AIR MIX DOOR MOTOR

HAC-111

< DTC/CIRCUIT DIAGNOSIS >

[AUTO A/C (WITH HEAT PUMP)]

C

D

E

F

G

H

J

K

L

M

A

B

HAC

N

O

P

Check A/C relay circuit. Refer to 

EVC-385, "Diagnosis Procedure"

.

Is the inspection result normal?

YES

>> Repair harness or connector between A/C relay and air mix door motor.

NO

>> Repair or replace malfunctioning components.

3.

CHECK AIR MIX DOOR MOTOR DRIVE SIGNAL CIRCUIT FOR OPEN

1. Turn power switch OFF.

2. Disconnect A/C auto amp. connector.

3. Check continuity between air mix 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 AIR MIX DOOR MOTOR DRIVE SIGNAL CIRCUIT FOR SHORT

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

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Repair harness or connector.

5.

CHECK AIR MIX DOOR MOTOR

Check air mix door motor. Refer to 

HAC-111, "Component Inspection"

.

Is the inspection result normal?

YES

>> Replace A/C auto amp. Refer to 

HAC-187, "Removal and Installation"

.

NO

>> Replace air mix door motor. Refer to 

HAC-205, "AIR MIX DOOR MOTOR : Removal and Installa-

tion"

.

Component Inspection

INFOID:0000000010121823

1.

CHECK AIR MIX DOOR MOTOR

1. Remove air mix door motor. Refer to 

HAC-205, "AIR MIX DOOR MOTOR : Removal and Installation"

.

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

Air mix door motor

A/C auto amp.

Continuity

Connector

Terminal

Connector

Terminal

M146

1

M55

9

Yes

2

8

5

7

6

6

Air mix door motor

—

Continuity

Connector

Terminal

M146

1

Ground

No

2

5

6

Terminal

Resistance (

Ω)

(Approx.)

4

1

90

2

5

6

HAC-112

< DTC/CIRCUIT DIAGNOSIS >

[AUTO A/C (WITH HEAT PUMP)]

B27A2, B27A3, B27A4, B27A5 AIR MIX DOOR MOTOR

Is the inspection result normal?

YES

>> Inspection End.

NO

>> Replace air mix door motor. Refer to 

HAC-205, "AIR MIX DOOR MOTOR : Removal and Installa-

tion"

.

B27A6, B27A7, B27A8, B27A9 MODE DOOR MOTOR

HAC-113

< DTC/CIRCUIT DIAGNOSIS >

[AUTO A/C (WITH HEAT PUMP)]

C

D

E

F

G

H

J

K

L

M

A

B

HAC

N

O

P

B27A6, B27A7, B27A8, B27A9 MODE DOOR MOTOR

DTC Logic

INFOID:0000000010121824

DTC DETECTION LOGIC 

NOTE:

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

HAC-

87, "DTC Logic"

.

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

HAC-88,

"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 power switch ON.

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

3. Check DTC.
Is DTC detected?

YES

>> Refer to 

HAC-113, "Diagnosis Procedure"

.

NO

>> Inspection End.

Diagnosis Procedure

INFOID:0000000010121825

Regarding Wiring Diagram information, refer to 

HAC-61, "Wiring Diagram"

.

1.

CHECK MODE DOOR MOTOR POWER SUPPLY

1. Turn power switch OFF.

2. Disconnect mode door motor connector.

3. Turn power switch ON.

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

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> GO TO 2.

2.

CHECK A/C RELAY CIRCUIT

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

(Approx.)

Mode door motor

Connector

Terminal

M142

4

Ground

Battery voltage

HAC-114

< DTC/CIRCUIT DIAGNOSIS >

[AUTO A/C (WITH HEAT PUMP)]

B27A6, B27A7, B27A8, B27A9 MODE DOOR MOTOR

Check A/C relay circuit. Refer to 

EVC-385, "Diagnosis Procedure"

.

Is the inspection result normal?

YES

>> Repair harness or connector between A/C relay and mode door motor.

NO

>> Repair or replace malfunctioning components.

3.

CHECK MODE DOOR MOTOR DRIVE SIGNAL CIRCUIT FOR OPEN

1. Turn power 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 4.

NO

>> Repair harness or connector.

4.

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 5.

NO

>> Repair harness or connector.

5.

CHECK MODE DOOR MOTOR

Check mode door motor. Refer to 

HAC-114, "Component Inspection"

.

Is the inspection result normal?

YES

>> Replace A/C auto amp. Refer to 

HAC-187, "Removal and Installation"

.

NO

>> Replace mode door motor. Refer to 

HAC-205, "MODE DOOR MOTOR : Removal and Installa-

tion"

.

Component Inspection

INFOID:0000000010121826

1.

CHECK MODE DOOR MOTOR

1. Remove mode door motor. Refer to 

HAC-205, "MODE DOOR MOTOR : Removal and Installation"

.

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

Mode door motor

A/C auto amp.

Continuity

Connector

Terminal

Connector

Terminal

M142

1

M55

5

Yes

2

4

5

3

6

2

Mode door motor

—

Continuity

Connector

Terminal

M142

1

Ground

No

2

5

6

Terminal

Resistance (

Ω)

(Approx.)

4

1

90

2

5

6