Nissan Leaf. Manual - part 792

B27F5 REFRIGERANT CHANNEL SWITCHING 3 WAY TYPE VALVE

HAC-171

< 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

1. Turn power switch OFF.

2. Disconnect heat pump control unit connector and A/C auto amp. connector.

3. Check continuity between heat pump control unit harness connector and A/C auto amp. harness connec-

tor.

NOTE:

Check for any adhering foreign substances, cracking, or damage on the heat pump control unit terminal

and A/C auto amp. harness connector terminal.

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> Repair harness or connector.

7.

CHECK HEAT PUMP CONTROL UNIT COMMUNICATION LINE FOR SHORT

Check continuity between heat pump control unit harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 8.

NO

>> Repair harness or connector.

8.

CHECK REFRIGERANT CHANNEL SWITCHING 3 WAY TYPE VALVE

Check refrigerant channel switching 3 way type valve. Refer to 

HAC-165, "Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 9.

NO

>> Replace high-pressure cooler pipe assembly. Refer to 

HA-47, "2-WAY VALVE AND 3-WAY VALVE

ASSEMBLY : Removal and Installation"

.

9.

PERFORM DTC CONFIRMATION PROCEDURE

Perform DTC confirmation procedure. Refer to 

HAC-169, "DTC Logic"

.

Is DTC B27F5 detected?

YES

>> Replace heat pump control unit. Refer to 

HAC-188, "Removal and Installation"

.

NO

>> Check intermittent incident. Refer to 

GI-53, "Intermittent Incident"

.

Heat pump control unit

A/C auto amp.

Continuity

Connector

Terminal

Connector

Terminal

M102

1

M55

40

Yes

Heat pump control unit

—

Continuity

Connector

Terminal

M102

1

Ground

No

HAC-172

< DTC/CIRCUIT DIAGNOSIS >

[AUTO A/C (WITH HEAT PUMP)]

B27FF A/C AUTO AMP.

B27FF A/C AUTO AMP.

DTC Logic

INFOID:0000000010121876

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT

1. Turn power switch OFF.

2. Set the vehicle to READY.

3. Operate the automatic air conditioning system.

4. Set the temperature to full cold and wait at least 2 seconds.

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

6. Check DTC.
Is DTC detected?

YES

>> Refer to 

HAC-172, "Diagnosis Procedure"

.

NO

>> Inspection End.

Diagnosis Procedure

INFOID:0000000010121877

1.

PERFORM A/C AUTO AMP. CONFIGURATION

With CONSULT

1. Turn power switch ON

2. Use CONSULT and perform configuration (control unit setting) of “HVAC”. Refer to 

HAC-81, "Work Proce-

dure"

.

>> Inspection End.

DTC

Items

(CONSULT screen terms)

DTC detection condition

Possible cause

B27FF

CONFIG NOT IMPLEM

When A/C auto amp. configuration (control unit 
setting) is not performed.

A/C auto amp (Not performed config-
uration)

POWER SUPPLY AND GROUND CIRCUIT

HAC-173

< 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

POWER SUPPLY AND GROUND CIRCUIT

A/C AUTO AMP.
A/C AUTO AMP. : Diagnosis Procedure

INFOID:0000000010121878

Regarding Wiring Diagram information, refer to 

HAC-61, "Wiring Diagram"

.

1.

CHECK SYMPTOM

Check symptom (A or B).

Which symptom is detected?

A

>> GO TO 2.

B

>> GO TO 4.

2.

CHECK FUSE

1. Turn power switch OFF.

2. Check 10A fuse [No. 3, located in fuse block (J/B)].

NOTE:

Refer to 

PG-78, "Terminal Arrangement"

.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> Replace the blown fuse after repairing the affected circuit if a fuse is blown. 

3.

CHECK A/C AUTO AMP. POWER SWITCH POWER SUPPLY

1. Disconnect A/C auto amp. connector. 

2. Turn power switch ON. 

3. Check voltage between A/C auto amp. harness connector and ground. 

Is the inspection result normal?

YES

>> GO TO 6.

NO

>> Repair harness or connector between A/C auto amp. and fuse.

4.

CHECK FUSE

1. Turn power switch OFF.

2. Check 10A fuse [No.13, located in fuse block (J/B)].

NOTE:

Refer to 

PG-78, "Terminal Arrangement"

.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Replace the blown fuse after repairing the affected circuit. 

5.

CHECK A/C AUTO AMP. BATTERY POWER SUPPLY

1. Disconnect A/C auto amp. connector. 

Symptom

A

• Air conditioning system does not activate.
• Air conditioning system does cannot be controlled.
• Operation status of air conditioning system is not indicated on display.

B

• Memory function does not operate normally.
• The setting is not maintained. (It returns to the initial condition)

+

−

Voltage

(Approx.)

A/C auto amp.

Connector

Terminal

M55

32

Ground

9 V or more

HAC-174

< DTC/CIRCUIT DIAGNOSIS >

[AUTO A/C (WITH HEAT PUMP)]

POWER SUPPLY AND GROUND CIRCUIT

2. Check voltage between A/C auto amp. harness connector and ground. 

Is the inspection result normal?

YES

>> GO TO 6.

NO

>> Repair harness or connector between A/C auto amp. and fuse.

6.

CHECK A/C AUTO AMP. GROUND CIRCUIT FOR OPEN

1. Turn power switch OFF.

2. Check continuity between A/C auto amp. harness connector and ground. 

Is the inspection result normal?

YES

>> Replace A/C auto amp. Refer to 

HAC-187, "Removal and Installation"

.

NO

>> Repair harness or connector.

+

−

Voltage

(Approx.)

A/C auto amp.

Connector

Terminal

M55

31

Ground

Battery voltage

A/C auto amp.

—

Continuity

Connector

Terminal

M55

10

Ground

Yes