Nissan Leaf. Manual - part 827

B278C, B278D ELECTRIC COMPRESSOR

HAC-311

< DTC/CIRCUIT DIAGNOSIS >

[AUTO A/C (WITHOUT HEAT PUMP)]

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HAC

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WARNING:

Disconnect the high voltage. Refer to 

GI-33, "How to Disconnect High Voltage"

.

Check voltage in high voltage circuit. (Check that condenser are discharged.)

1. Lift up the vehicle and remove the Li-ion battery under covers. Refer to 

EVB-181, "Exploded View"

.

2. Disconnect high voltage harness connector and PTC heater harness connector from front side of Li-ion

battery. Refer to 

EVB-181, "Removal and Installation"

.

3. Measure voltage between high voltage harness connector terminals and PTC heater harness connector

terminals.

DANGER:

 

 Touching high voltage components without using the appropriate protective equipment will

cause electrocution.

CAUTION:

For voltage measurements, use a tester which can measure to 500 V or higher.

>> GO TO 2.

2.

CHECK ELECTRIC COMPRESSOR COMMUNICATION LINE FOR OPEN

1. Turn power switch OFF.

2. Disconnect electric compressor and A/C auto amp. connector.

3. Check continuity between electric compressor harness connector and A/C auto amp. harness connector.

NOTE:

Check for any adhering foreign substances, cracking, or damage on the electric compressor terminal and

A/C auto amp. harness connector terminal.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> Repair harness or connector.

3.

CHECK ELECTRIC COMPRESSOR COMMUNICATION LINE FOR SHORT

Check continuity between electric compressor harness connector and ground.

Standard

: 5 V or less 

JPCIA0296ZZ

Electric compressor

A/C auto amp.

Continuity

Connector

Terminal

Connector

Terminal

F10

7

M55

14

Yes

9

18

Electric compressor

Ground

Continuity

Connector

Terminal

F10

7

No

9

HAC-312

< DTC/CIRCUIT DIAGNOSIS >

[AUTO A/C (WITHOUT HEAT PUMP)]

B278C, B278D ELECTRIC COMPRESSOR

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Repair harness or connector.

4.

CHECK ELECTRIC COMPRESSOR POWER SUPPLY

1. Disconnect electric compressor connector.

2. Turn power switch ON.

3. Check voltage between electric compressor harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> GO TO 6.

5.

CHECK ELECTRIC COMPRESSOR GROUND CIRCUIT

1. Turn power switch OFF.

2. Check continuity between electric compressor harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> Repair harness or connector.

6.

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 electric compressor.

NO

>> Repair or replace malfunctioning components.

7.

CHECK PDM (POWER DELIVERY MODULE)

Check PDM (power delivery module). Refer to 

EVC-125, "Work Flow"

.

Is the inspection result normal?

YES

>> GO TO 8.

NO

>> Repair or replace malfunctioning components.

8.

CHECK ELECTRIC COMPRESSOR HIGH VOLTAGE HARNESS POWER SUPPLY CIRCUIT FOR OPEN

1. Disconnect electric compressor and Li-ion battery connector.

2. Check continuity between electric compressor high voltage harness connector and Li-ion battery high volt-

age harness connector.

Is the inspection result normal?

YES

>> GO TO 9.

NO

>> Replace high voltage harness between electric compressor and PDM (power delivery module),

and between PDM (power delivery module) and Li-ion battery.

9.

CHECK ELECTRIC COMPRESSOR HIGH VOLTAGE HARNESS GROUND CIRCUIT

+

−

Voltage

(Approx.)

Electric compressor

Connector

Terminal

F10

10

Ground

Battery voltage

Electric compressor

Ground

Continuity

Connector

Terminal

F10

8

Yes

Electric compressor

Li-ion battery

Continuity

Connector

Terminal

Connector

Terminal

H1

1

H3

37

Yes

B278C, B278D ELECTRIC COMPRESSOR

HAC-313

< DTC/CIRCUIT DIAGNOSIS >

[AUTO A/C (WITHOUT HEAT PUMP)]

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Check continuity between electric compressor high voltage harness connector and Li-ion battery high voltage

harness connector.

Is the inspection result normal?

YES

>> GO TO 10.

NO

>> Replace high voltage harness between electric compressor and PDM (power delivery module),

and between PDM (power delivery module) and Li-ion battery.

10.

CHECK A/C AUTO AMP.

With CONSULT

1. Reconnect all harness connectors disconnected.

2. Set the vehicle to READY.

3. Using CONSULT, perform “MODE1” of “HVAC TEST” in “Active Test” of “HVAC”. Refer to 

HAC-242,

"CONSULT Function"

.

4. Check that the electric compressor operates normally.
Is the inspection result normal?

YES

>> Inspection End.

NO

>> Replace A/C auto amp. Refer to 

HAC-347, "Removal and Installation"

. Then GO TO 11.

11.

PERFORM DTC CONFIRMATION PROCEDURE

Perform DTC confirmation procedure. Refer to 

HAC-310, "DTC Logic"

.

Is DTC B278C detected?

YES

>> Replace electric compressor. Refer to 

HA-95, "Removal and Installation"

.

NO

>> Inspection End.

Electric compressor

Li-ion battery

Continuity

Connector

Terminal

Connector

Terminal

H1

2

H3

38

Yes

HAC-314

< DTC/CIRCUIT DIAGNOSIS >

[AUTO A/C (WITHOUT HEAT PUMP)]

B2791 ELECTRIC COMPRESSOR

B2791 ELECTRIC COMPRESSOR

DTC Logic

INFOID:0000000010122024

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-314, "Diagnosis Procedure"

.

NO

>> Inspection End.

Diagnosis Procedure

INFOID:0000000010122025

1.

CHECK REFRIGERANT FOR LEAKAGES

Check refrigerant for leakages. Refer to 

HA-84, "Check Refrigerant Leakage"

.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Repair or replace malfunctioning parts.

2.

CHECK COOLING FAN OPERATION

1. Set the vehicle to READY.

2. Operate the automatic air conditioning system.

3. Check that the cooling fan is operating.
Is the inspection result normal?

YES

>> GO TO 3.

NO

>> Check cooling fan. Refer to 

EVC-367, "Component Function Check"

.

3.

CHECK REFRIGERANT CYCLE

Check refrigerant cycle. Refer to 

HA-89, "Inspection"

.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Repair or replace malfunctioning parts.

4.

CHECK LI-ION BATTERY

Check Li-ion battery. Refer to 

EVB-69, "Work Flow"

.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Repair or replace malfunctioning parts.

5.

CHECK PDM (POWER DELIVERY MODULE)

DTC

Items

(CONSULT screen terms)

DTC detection condition

Possible cause

B2791

COMP LOW SPEED HIGH 
LOAD

When the driving load of the electric compres-
sor reaches a maximum value during slow rota-
tion.

• Electric compressor
• Cooling fan
• Li-ion battery
• PDM
• Overfilled refrigerant