Nissan Leaf. Manual - part 790

B27F3 REFRIGERANT CHANNEL SWITCHING 3 WAY TYPE VALVE

HAC-163

< 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

B27F3 REFRIGERANT CHANNEL SWITCHING 3 WAY TYPE VALVE

DTC Logic

INFOID:0000000010121869

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"

.

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 5 seconds.

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

6. Check DTC.
Is DTC detected?

YES

>> Refer to 

HAC-163, "Diagnosis Procedure"

.

NO

>> Inspection End.

Diagnosis Procedure

INFOID:0000000010121870

Regarding Wiring Diagram information, refer to 

HAC-61, "Wiring Diagram"

.

NOTE:

After diagnosis is completed, reconnect all harness connectors. Then, use CONSULT to enter “Active Test” of

“HVAC”, and perform “MODE2” (cooling operation) and “MODE5” (heating operation) of “HVAC TEST” for the

maximum of 10 minutes. (Refer to 

HAC-47, "CONSULT Function"

.) Check that cool air blows during cooling

operation, and that warm air blows during heating operation.

1.

CHECK REFRIGERANT CHANNEL SWITCHING 3 WAY TYPE VALVE CONTROL CIRCUIT FOR OPEN

1. Turn power switch OFF.

2. Disconnect refrigerant channel switching 3 way type valve connector and heat pump control unit connec-

tor.

3. Check continuity between refrigerant channel switching 3 way type valve harness connector and heat

pump control unit harness connector.

NOTE:

Check for any adhering foreign substances, cracking, or damage on the refrigerant channel switching 3

way type valve terminal and heat pump control unit harness connector terminal.

DTC

Items

(CONSULT screen terms)

DTC detection condition

Possible cause

B27F3

3-WAY TYPE VALVE CIRC

When the heat pump control unit detects a mal-
function of the refrigerant channel switching 3 
way type valve control signal status, compared 
to the valve status of the control that is being 
judged.

• Refrigerant channel switching 3 

way type valve

• Heat pump control unit
• Harness or connectors

(The heat pump control unit circuit 
or refrigerant channel switching 3 
way type valve circuit is open or 
shorted.)

HAC-164

< DTC/CIRCUIT DIAGNOSIS >

[AUTO A/C (WITH HEAT PUMP)]

B27F3 REFRIGERANT CHANNEL SWITCHING 3 WAY TYPE VALVE

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Repair harness or connector.

2.

CHECK REFRIGERANT CHANNEL SWITCHING 3 WAY TYPE VALVE CONTROL CIRCUIT FOR SHORT

(BATTERY)
1. Turn power switch ON.

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

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> Repair harness or connector.

3.

CHECK REFRIGERANT CHANNEL SWITCHING 3 WAY TYPE VALVE CONTROL CIRCUIT FOR SHORT

(GROUND)
1. Turn power switch OFF.

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

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Repair harness or connector.

4.

CHECK REFRIGERANT CHANNEL SWITCHING 3 WAY TYPE VALVE POWER SUPPLY

1. Turn power switch ON.

2. Check continuity between refrigerant channel switching 3 way type valve harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 6.

NO

>> GO TO 5.

5.

CHECK A/C RELAY CIRCUIT

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 refrigerant channel switching 3 way type

valve.

NO

>> Repair or replace malfunctioning components.

6.

CHECK HEAT PUMP CONTROL UNIT COMMUNICATION LINE FOR OPEN

Refrigerant channel switching 3 way type valve

Heat pump control unit

Continuity

Connector

Terminal

Connector

Terminal

E91

2

M102

7

Yes

+

−

Voltage

(Approx.)

Heat pump control unit

Connector

Terminal

M102

7

Ground

0 V

Heat pump control unit

—

Continuity

Connector

Terminal

M102

7

Ground

No

+

−

Voltage

(Approx.)

Refrigerant channel switching 3 way type valve

Connector

Terminal

E91

1

Ground

Battery voltage

B27F3 REFRIGERANT CHANNEL SWITCHING 3 WAY TYPE VALVE

HAC-165

< 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-163, "DTC Logic"

.

Is DTC B27F3 detected?

YES

>> Replace heat pump control unit. Refer to 

HAC-188, "Removal and Installation"

.

NO

>> Check intermittent incident. Refer to 

GI-53, "Intermittent Incident"

.

Component Inspection

INFOID:0000000010121871

1.

CHECK REFRIGERANT CHANNEL SWITCHING 3 WAY TYPE VALVE

1. Turn power switch OFF.

2. Disconnect refrigerant channel switching 3 way type valve connector.

3. Check resistance between refrigerant channel switching 3 way type valve terminals. Refer to applicable

table for the normal value. 

Is the inspection result normal?

YES

>> Inspection End.

NO

>> Replace refrigerant channel switching 3 way type valve (high-pressure cooler pipe assembly).

Refer to 

HA-47, "2-WAY VALVE AND 3-WAY VALVE ASSEMBLY : Removal and Installation"

.

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

Terminal

Resistance (

Ω)

1

2

13.6 

± 1.4

HAC-166

< DTC/CIRCUIT DIAGNOSIS >

[AUTO A/C (WITH HEAT PUMP)]

B27F4 REFRIGERANT CHANNEL SWITCHING 3 WAY TYPE VALVE

B27F4 REFRIGERANT CHANNEL SWITCHING 3 WAY TYPE VALVE

DTC Logic

INFOID:0000000010121872

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"

.

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 hot and wait at least 5 seconds.

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

6. Check DTC.
Is DTC detected?

YES

>> Refer to 

HAC-166, "Diagnosis Procedure"

.

NO

>> Inspection End.

Diagnosis Procedure

INFOID:0000000010121873

Regarding Wiring Diagram information, refer to 

HAC-61, "Wiring Diagram"

.

NOTE:

After diagnosis is completed, reconnect all harness connectors. Then, use CONSULT to enter “Active Test” of

“HVAC”, and perform “MODE2” (cooling operation) and “MODE5” (heating operation) of “HVAC TEST” for the

maximum of 10 minutes. (Refer to 

HAC-47, "CONSULT Function"

.) Check that cool air blows during cooling

operation, and that warm air blows during heating operation.

1.

CHECK REFRIGERANT CHANNEL SWITCHING 3 WAY TYPE VALVE CONTROL CIRCUIT FOR OPEN

1. Turn power switch OFF.

2. Disconnect refrigerant channel switching 3 way type valve connector and heat pump control unit connec-

tor.

3. Check continuity between refrigerant channel switching 3 way type valve harness connector and heat

pump control unit harness connector.

NOTE:

Check for any adhering foreign substances, cracking, or damage on the refrigerant channel switching 3

way type valve terminal and heat pump control unit harness connector terminal.

DTC

Items

(CONSULT screen terms)

DTC detection condition

Possible cause

B27F4

3-WAY TYPE VALVE CIRC

When the heat pump control unit detects a mal-
function of the refrigerant channel switching 3 
way type valve control signal status, compared 
to the valve status of the control that is being 
judged.

• Refrigerant channel switching 3 

way type valve

• Heat pump control unit
• Harness or connectors

(The heat pump control unit circuit 
or refrigerant channel switching 3 
way type valve circuit is open or 
shorted.)