Infiniti QX56 (Z62). Manual - part 549

EC-174

< DTC/CIRCUIT DIAGNOSIS >

[VK56VD]

U0113, U1003 CAN COMM CIRCUIT

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

3.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-40, "Intermittent Incident"

.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Repair or replace.

4.

REPLACE VVEL CONTROL MODULE

Replace VVEL control module. Refer to 

EC-536, "Removal and Installation"

.

>> 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-173, "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-173, "DTC Logic"

.

Is the DTC U0113 or U1003 displayed again?

YES 

>> GO TO 6.

NO

>> INSPECTION END

6.

REPLACE ECM

Replace ECM. Refer to 

EC-535, "Removal and Installation"

.

>> INSPECTION END

U1024 CAN COMM CIRCUIT

EC-175

< DTC/CIRCUIT DIAGNOSIS >

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U1024 CAN COMM CIRCUIT

DTC Logic

INFOID:0000000006217770

DTC DETECTION LOGIC

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

EC-378, "DTC Logic"

.

DTC CONFIRMATION PROCEDURE

1.

PRECONDITIONING 

TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is 10 V or more 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-175, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000006217771

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.
• Harness for open or short between ECM and VVEL control module
• Loose or poor connection for each connector and harness

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

DTC No.

Trouble diagnosis name

(Trouble diagnosis content)

DTC detecting condition

Possible cause

U1024

VVEL CAN COMM CIRCUIT
(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

E80

161

F56

24

Existed

166

11

EC-176

< DTC/CIRCUIT DIAGNOSIS >

[VK56VD]

U1024 CAN COMM CIRCUIT

3.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-40, "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 additional service when replacing VVEL control module. Refer to 

EC-144, "Work Procedure"

.

>> 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-175, "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-175, "DTC Logic"

.

Is the DTC U1024 displayed again?

YES

>> GO TO 6.

NO >> INSPECTION 

END

6.

REPLACE ECM

1.

Replace ECM.

2.

Perform additional service when replacing ECM. Refer to 

EC-143, "Work Procedure"

.

>> INSPECTION END

P0011, P0021 IVT CONTROL

EC-177

< DTC/CIRCUIT DIAGNOSIS >

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P0011, P0021 IVT CONTROL

DTC Logic

INFOID:0000000006217772

DTC DETECTION LOGIC

NOTE:
If DTC P0011 or P0021 is displayed with DTC P0075 or P0081, first perform the trouble diagnosis for
DTC P0075, P0081. Refer to 

EC-193, "DTC Logic"

.

DTC CONFIRMATION PROCEDURE

1.

PRECONDITIONING

1.

Turn ignition switch OFF and wait at least 10 seconds.

2.

Turn ignition switch ON.

3.

Turn ignition switch OFF and wait at least 10 seconds.

TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is 11 V or more at idle.

>> GO TO 2.

2.

PERFORM DTC CONFIRMATION PROCEDURE-I

 WITH CONSULT-III

1.

Turn ignition switch ON and select “DATA MONITOR” mode with CONSULT-III.

2.

Start engine and warm it up to the normal operating temperature.

3.

Maintain the following conditions for at least 6 consecutive seconds.
Hold the accelerator pedal as steady as possible.

4.

Let engine idle for 25 seconds.

5.

Check 1st trip DTC.

 WITH GST

Follow the procedure “With CONSULT-III” above.
Is 1st trip DTC detected?

YES

>> Go to 

EC-178, "Diagnosis Procedure"

NO

>> GO TO 3.

3.

PERFORM DTC CONFIRMATION PROCEDURE-II

 WITH CONSULT-III

1.

Select “DATA MONITOR” mode with CONSULT-III.

2.

Maintain the following conditions for at least 20 consecutive seconds.

DTC No.

Trouble diagnosis

(Trouble diagnosis con-

tent)

Detecting condition

Possible cause

P0011

INT/V TIM CONT-B1
[Intake valve timing control 
performance (bank 1)]

There is a gap between angle of target 
and phase-control angle degree.

• Crankshaft position sensor
• Camshaft position sensor
• Intake valve timing control solenoid valve
• Accumulation of debris to the signal pick-up 

portion of the camshaft

• Timing chain installation
• Foreign matter caught in the oil groove for in-

take valve timing control

P0021

INT/V TIM CONT-B2
[Intake valve timing control 
performance (bank 2)]

ENG SPEED

Less than 2,000 rpm (A constant rotation is maintained.)

COOLAN TEMP/S

More than 70

°

C (158

°

F)

Selector lever

P or N position

ENG SPEED

1,500 - 3,175 rpm (A constant rotation is maintained.)

COOLAN TEMP/S

More than 70

°

C (158

°

F)