Nissan Altima HL32 Hybrid. Manual - part 284

EC-120

< COMPONENT DIAGNOSIS >

[QR25DE]

U0293, U1020 CAN COMM CIRCUIT

U0293, U1020 CAN COMM CIRCUIT

DTC Logic

INFOID:0000000004211356

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

PERFORM DTC CONFIRMATION PROCEDURE

1. Turn ignition switch ON and wait at least 3 seconds.

2. Check DTC.
Is DTC detected?

YES

>>

EC-120, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000004211357

Go to 

LAN-4, "Description"

.

DTC No.

Trouble diagnosis 

name

DTC detecting condition

Possible cause

U0293

Lost communication 
with HV ECU

CAN communication signal of OBD (emission related 
diagnosis) is not received between HV ECU and 
ECM for 1 second or more.

• HEV SYSTEM CAN communication 

line between HV ECU and ECM

• HEV SYSTEM CAN communication 

line short

U1020

CAN communication signal other than OBD (emis-
sion related diagnosis) is not received between HV 
ECU and ECM for 1 second or more.

U0400, U1021 CAN COMM DATA

EC-121

< COMPONENT DIAGNOSIS >

[QR25DE]

C

D

E

F

G

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EC

N

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U0400, U1021 CAN COMM DATA

DTC Logic

INFOID:0000000004211358

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

PERFORM DTC CONFIRMATION PROCEDURE

1. Turn ignition switch ON and wait at least 3 seconds.

2. Check DTC.
Is DTC detected?

YES

>> Go to 

EC-121, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000004211359

1.

CHECK HEV SYSTEM CAN COMMUNICATION CIRCUIT

Refer to 

LAN-53, "Trouble Diagnosis Procedure"

.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Repair or replace.

2.

REPLACE ECM

1. Replace ECM.

2. Go to 

EC-14, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT : Special Repair Require-

ment"

.

>> GO TO 3.

3.

PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT-III

1. Turn ignition switch ON.

2. Select “SELF-DIAG RESULTS” mode with CONSULT-III.

3. Touch “ERASE”.

4. Perform DTC CONFIRMATION PROCEDURE.

See 

EC-121, "DTC Logic"

.

5. Check DTC.

With GST

1. Turn ignition switch ON.

2. Select “Service $04” with GST.

3. Perform DTC CONFIRMATION PROCEDURE.

See 

EC-121, "DTC Logic"

.

4. Check DTC.
Is the DTC U0400 or U1021 displayed again?

YES

>> GO TO 4.

NO

>> INSPECTION END

4.

REPLACE HV ECU

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

U0400

Invalid data received from 
hybrid vehicle control ECU

SUM data on CAN signal of OBD (emission re-
lated diagnosis) from HV ECU is different from 
SUM data calculated by ECM.

• Harness or connectors

(HEV SYSTEM CAN communication 
line is open or shorted)

• ECM
• HV ECU

U1021

SUM data on CAN signal other than OBD 
(emission related diagnosis) from HV ECU is 
different from SUM data calculated by ECM.

EC-122

< COMPONENT DIAGNOSIS >

[QR25DE]

U0400, U1021 CAN COMM DATA

1. Replace HV ECU.

2. Go to 

HBC-12, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT : Special Repair Require-

ment"

.

>> INSPECTION END

U0418, U1023 CAN COMM DATA

EC-123

< COMPONENT DIAGNOSIS >

[QR25DE]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

U0418, U1023 CAN COMM DATA

DTC Logic

INFOID:0000000004211360

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

PERFORM DTC CONFIRMATION PROCEDURE

1. Turn ignition switch ON and wait at least 3 seconds.

2. Check DTC.
Is DTC detected?

YES

>> Go to 

EC-123, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000004211361

1.

CHECK HEV SYSTEM CAN COMMUNICATION CIRCUIT

Refer to 

LAN-53, "Trouble Diagnosis Procedure"

.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Repair or replace.

2.

REPLACE ECM

1. Replace ECM.

2. Go to 

EC-14, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT : Special Repair Require-

ment"

.

>> GO TO 3.

3.

PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT-III

1. Turn ignition switch ON.

2. Select “SELF-DIAG RESULTS” mode with CONSULT-III.

3. Touch “ERASE”.

4. Perform DTC CONFIRMATION PROCEDURE.

See 

EC-123, "DTC Logic"

.

5. Check DTC.

With GST

1. Turn ignition switch ON.

2. Select “Service $04” with GST.

3. Perform DTC CONFIRMATION PROCEDURE.

See 

EC-123, "DTC Logic"

.

4. Check DTC.
Is the DTC U0418 or U1023 displayed again?

YES

>> GO TO 4.

NO

>> INSPECTION END

4.

REPLACE BRAKE ECU

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

U0418

Invalid data received from 
brake ECU

SUM data on CAN signal of OBD (emission re-
lated diagnosis) from brake ECU is different 
from SUM data calculated by ECM.

• Harness or connectors

(HEV SYSTEM CAN communication 
line is open or shorted)

• ECM
• Brake  ECU

U1023

SUM data on CAN signal other than OBD 
(emission related diagnosis) from brake ECU is 
different from SUM data calculated by ECM.