Nissan Leaf. Manual - part 819

U1010 CONTROL UNIT (CAN)

HAC-279

< DTC/CIRCUIT DIAGNOSIS >

[AUTO A/C (WITHOUT HEAT PUMP)]

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U1010 CONTROL UNIT (CAN)

Description

INFOID:0000000010121982

Initial diagnosis of A/C auto amp.

DTC Logic

INFOID:0000000010121983

DTC DETECTION LOGIC 

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-279, "Diagnosis Procedure"

.

NO

>> Inspection End.

Diagnosis Procedure

INFOID:0000000010121984

1.

REPLACE A/C AUTO AMP.

Replace A/C auto amp. Refer to 

HAC-347, "Removal and Installation"

.

>> Inspection End.

DTC

Items

(CONSULT screen terms)

DTC detection condition

Possible cause

U1010

CONTROL UNIT (CAN)

When detecting error during the initial diagnosis of CAN 
controller of A/C auto amp.

A/C auto amp.

HAC-280

< DTC/CIRCUIT DIAGNOSIS >

[AUTO A/C (WITHOUT HEAT PUMP)]

B2578, B2579 IN-VEHICLE SENSOR

B2578, B2579 IN-VEHICLE SENSOR

DTC Logic

INFOID:0000000010121985

DTC DETECTION LOGIC 

NOTE:

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

HAC-

278, "DTC Logic"

.

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

HAC-279,

"DTC Logic"

.

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-280, "Diagnosis Procedure"

.

NO

>> Inspection End.

Diagnosis Procedure

INFOID:0000000010121986

Regarding Wiring Diagram information, refer to 

HAC-253, "Wiring Diagram"

.

1.

CHECK IN-VEHICLE SENSOR VOLTAGE SIGNAL

1. Turn power switch ON.

2. Operate the automatic air conditioning system.

3. Check voltage signal between A/C auto amp. harness connector terminals.

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> GO TO 2.

2.

CHECK IN-VEHICLE SENSOR POWER SUPPLY

DTC

Items

(CONSULT screen terms)

DTC detection condition

Possible cause

B2578

IN-VEHICLE SENSOR

The in-vehicle sensor recognition temperature 
is too high [more than 100

°C (212°F)].

• In-vehicle sensor
• A/C auto amp.
• Harness or connectors

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

B2579

The in-vehicle sensor recognition temperature 
is too low [less than 

−42°C (−44°F)].

A/C auto amp.

Test condition

Voltage signal

Connector

+

−

Terminal

M55

33

10

• Power switch ON
• When air conditioner is op-

erating

JSIIA1662ZZ

B2578, B2579 IN-VEHICLE SENSOR

HAC-281

< DTC/CIRCUIT DIAGNOSIS >

[AUTO A/C (WITHOUT HEAT PUMP)]

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1. Turn power switch OFF.

2. Disconnect in-vehicle sensor connector. 

3. Turn power switch ON.

4. Check voltage between in-vehicle sensor harness connector and ground. 

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> GO TO 5.

3.

CHECK IN-VEHICLE SENSOR GROUND CIRCUIT FOR OPEN

1. Turn power switch OFF.

2. Disconnect A/C auto amp. connector. 

3. Check continuity between in-vehicle sensor 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 IN-VEHICLE SENSOR

Check in-vehicle sensor. Refer to 

HAC-282, "Component Inspection"

.

Is the inspection result normal?

YES

>> Replace A/C auto amp. Refer to 

HAC-347, "Removal and Installation"

.

NO

>> Replace in-vehicle sensor. Refer to 

HAC-349, "Removal and Installation"

.

5.

CHECK IN-VEHICLE SENSOR POWER SUPPLY CIRCUIT FOR OPEN

1. Turn power switch OFF.

2. Disconnect A/C auto amp. connector. 

3. Check continuity between in-vehicle sensor harness connector and A/C auto amp. harness connector. 

Is the inspection result normal?

YES

>> GO TO 6.

NO

>> Repair harness or connector.

6.

CHECK IN-VEHICLE SENSOR POWER SUPPLY CIRCUIT FOR SHORT

Check continuity between in-vehicle sensor harness connector and ground. 

Is the inspection result normal?

YES

>> Replace A/C auto amp. Refer to 

HAC-347, "Removal and Installation"

.

NO

>> Repair harness or connector.

+

−

Voltage

(Approx.)

In-vehicle sensor

Connector

Terminal

M42

1

Ground

5 V

In-vehicle sensor

A/C auto amp.

Continuity

Connector

Terminal

Connector

Terminal

M42

2

M55

30

Yes

In-vehicle sensor

A/C auto amp.

Continuity

Connector

Terminal

Connector

Terminal

M42

1

M55

33

Yes

In-vehicle sensor

—

Continuity

Connector

Terminal

M42

1

Ground

No

HAC-282

< DTC/CIRCUIT DIAGNOSIS >

[AUTO A/C (WITHOUT HEAT PUMP)]

B2578, B2579 IN-VEHICLE SENSOR

7.

CHECK INTERMITTENT INCIDENT

Check intermittent incident. Refer to 

GI-53, "Intermittent Incident"

.

Is the inspection result normal?

YES

>> Replace A/C auto amp. Refer to 

HAC-347, "Removal and Installation"

.

NO

>> Repair or replace malfunctioning components.

Component Inspection

INFOID:0000000010121987

1.

CHECK IN-VEHICLE SENSOR

1. Remove in-vehicle sensor. Refer to 

HAC-349, "Removal and Installation"

. 

2. Check resistance between in-vehicle sensor terminals. Refer to applicable table for the normal value. 

Is the inspection result normal?

YES

>> Inspection End.

NO

>> Replace in-vehicle sensor. Refer to 

HAC-349, "Removal and Installation"

.

Terminal

Condition

Resistance: k

Ω

Temperature: 

°C (°F) 

1

2

 

−20 (−4)

16.43

 

−10 (14)

9.90

0 (32) 

6.19

10 (50)

4.01

20 (68)

2.67

25 (77)

2.20

30 (86)

1.83

40 (104)

1.28