Infiniti FX35, FX50 (S51). Manual - part 800

U0113, U1003 CAN COMM CIRCUIT

EC-741

< DTC/CIRCUIT DIAGNOSIS >

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2.

DETECT MALFUNCTIONING PART

Check the following.
• Harness connectors E10, F10
• Harness for open or short between ECM and VVEL control module

>> Repair open circuit, short to ground or short to power in harness or connectors.

3.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-36, "Intermittent Incident"

.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Repair or replace.

4.

REPLACE VVEL CONTROL MODULE

1.

Replace VVEL control module.

2.

Perform 

EC-579, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (VVEL CONTROL

MODULE) : Special Repair Requirement"

.

>> GO TO 5.

5.

PERFORM DTC CONFIRMATION PROCEDURE

 With CONSULT-III

1.

Reconnect all harness connectors disconnected.

2.

Turn ignition switch ON.

3.

Select “SELF DIAGNOSTIC RESULT” mode with CONSULT-III.

4.

Touch “ERASE”.

5.

Perform DTC Confirmation Procedure.
See 

EC-740, "DTC Logic"

.

 With GST

1.

Reconnect all harness connectors disconnected.

2.

Turn ignition switch ON.

3.

Select Service $04 with GST.

4.

Perform DTC Confirmation Procedure.
See 

EC-740, "DTC Logic"

.

Is the DTC U0113 or U1003 displayed again?

YES 

>> GO TO 6.

NO

>> INSPECTION END

6.

REPLACE ECM

1.

Replace ECM.

2.

Perform 

EC-579, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (ECM) : Special Repair

Requirement"

.

>> INSPECTION END

EC-742

< DTC/CIRCUIT DIAGNOSIS >

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U1001 CAN COMM CIRCUIT

U1001 CAN COMM CIRCUIT

Description

INFOID:0000000005237226

CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-
tiplex communication line with high data communication speed and excellent error detection ability. Many elec-
tronic control units are equipped onto a vehicle, and each control unit shares information and links with other
control units during operation (not independent). In CAN communication, control units are connected with 2
communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads required data only.

DTC Logic

INFOID:0000000005237227

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

PERFORM DTC CONFIRMATION PROCEDURE

1.

Turn ignition switch ON and wait at least 3 seconds.

2.

Check 1st trip DTC.

Is 1st trip DTC detected?

YES

>>

EC-742, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000005237228

Go to 

LAN-20, "Trouble Diagnosis Flow Chart"

.

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

U1001

CAN communication line

When ECM is not transmitting or receiving CAN 
communication signal other than OBD (emission 
related diagnosis) for 2 seconds or more.

• Harness or connectors

(CAN communication line is open or 
shorted)

U1024 CAN COMM CIRCUIT

EC-743

< DTC/CIRCUIT DIAGNOSIS >

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U1024 CAN COMM CIRCUIT

Description

INFOID:0000000005237229

CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-
tiplex communication line with high data communication speed and excellent error detection ability. ECM and
VVEL control module are connected with two communication lines (CAN H line and CAN L line) and transmit/
receive data. ECM shares information and links with the VVEL control module during operation.

DTC Logic

INFOID:0000000005237230

DTC DETECTION LOGIC

NOTE:
If DTC U1024 is displayed with DTC P0607, first perform the trouble diagnosis for DTC P0607. 
Refer to 

EC-964, "DTC Logic"

.

DTC CONFIRMATION PROCEDURE

1.

PRECONDITIONING 

TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10 V at idle.

>> GO TO 2.

2.

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-743, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000005237231

1.

CHECK VVEL CAN COMMUNICATION CIRCUIT

1.

Turn ignition switch OFF.

2.

Disconnect ECM harness connector.

3.

Disconnect VVEL control module harness connector.

4.

Check the continuity between ECM harness connector and VVEL control module harness connector.

5.

Also check harness for short to ground and short to power.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> GO TO 2.

2.

DETECT MALFUNCTIONING PART

Check the following.

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

U1024

VVEL CAN communication

• When VVEL control module cannot transmitting 

or receiving CAN communication signal with 
ECM for 2 seconds or more.

• When detecting error during the initial diagnosis 

of CAN controller of VVEL control module.

• Harness or connectors

(CAN communication line is open or 
shorted)

• ECM
• VVEL control module

ECM

VVEL control module

Continuity

Connector

Terminal

Connector

Terminal

F111

89

E16

24

Existed

M160

93

11

EC-744

< DTC/CIRCUIT DIAGNOSIS >

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U1024 CAN COMM CIRCUIT

• Harness connectors E10, F10
• Harness for open or short between ECM and VVEL control module

>> Repair open circuit, short to ground or short to power in harness or connectors.

3.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-36, "Intermittent Incident"

.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Repair or replace.

4.

REPLACE VVEL CONTROL MODULE

1.

Replace VVEL control module.

2.

Perform 

EC-579, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (VVEL CONTROL

MODULE) : Special Repair Requirement"

.

>> GO TO 5.

5.

PERFORM DTC CONFIRMATION PROCEDURE

 With CONSULT-III

1.

Reconnect all harness connectors disconnected.

2.

Turn ignition switch ON.

3.

Select “SELF DIAGNOSTIC RESULT” mode with CONSULT-III.

4.

Touch “ERASE”.

5.

Perform DTC Confirmation Procedure.
See 

EC-743, "DTC Logic"

.

 With GST

1.

Reconnect all harness connectors disconnected.

2.

Turn ignition switch ON.

3.

Select Service $04 with GST.

4.

Perform DTC Confirmation Procedure.
See 

EC-743, "DTC Logic"

.

Is the DTC U1024 displayed again?

YES

>> GO TO 6.

NO >> INSPECTION 

END

6.

REPLACE ECM

1.

Replace ECM.

2.

Go to 

EC-579, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (ECM) : Special Repair

Requirement"

.

>> INSPECTION END