Infiniti QX56 (Z62). Manual - part 540

EC-138

< BASIC INSPECTION >

[VK56VD]

DIAGNOSIS AND REPAIR WORKFLOW

needed, drive vehicle under the specific driving pattern. Refer to 

EC-157, "SRT Set Driving Pat-

tern"

.

Diagnostic Work Sheet

INFOID:0000000006217738

DESCRIPTION

There are many operating conditions that lead to the malfunction of
engine components. A good grasp of such conditions can make trou-
bleshooting faster and more accurate.
In general, each customer feels differently about symptoms. It is
important to fully understand the symptoms or conditions for a cus-
tomer complaint.
Utilize a diagnostic worksheet like the WORKSHEET SAMPLE
below in order to organize all the information for troubleshooting.
Some conditions may cause the MIL to illuminate or blink, and DTC
to be detected. Examples:
• Vehicle ran out of fuel, which caused the engine to misfire.
• Fuel filler cap was left off or incorrectly screwed on, allowing fuel to

evaporate into the atmosphere.

WORKSHEET SAMPLE

SEF907L

MTBL0017

BASIC INSPECTION

EC-139

< BASIC INSPECTION >

[VK56VD]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

BASIC INSPECTION

Work Procedure

INFOID:0000000006217739

1.

INSPECTION START

1.

Check service records for any recent repairs that may indicate a related malfunction, or a current need for
scheduled maintenance.

2.

Open engine hood and check the following:

-

Harness connectors for improper connections

-

Wiring harness for improper connections, pinches and cut

-

Vacuum hoses for splits, kinks and improper connections

-

Hoses and ducts for leakage

-

Air cleaner clogging

-

Gasket

3.

Check that electrical or mechanical loads are not applied.

-

Headlamp switch is OFF.

-

Air conditioner switch is OFF.

-

Rear window defogger switch is OFF.

-

Steering wheel is in the straight-ahead position, etc.

4.

Start engine and warm it up until engine coolant temperature
indicator points to the middle of gauge.
Check that engine stays below 1,000 rpm.

5.

Run engine at approximately 2,000 rpm for approximately 2 min-
utes under no load.

6.

Check that no DTC is displayed with CONSULT-III or GST.

Are any DTCs detected?

YES

>> GO TO 2.

NO

>> GO TO 3.

2.

REPAIR OR REPLACE

Repair or replace components as necessary according to corresponding Diagnosis Procedure.

>> GO TO 3

3.

CHECK IDLE SPEED

1.

Run engine at approximately 2,000 rpm for approximately 2 minutes under no load.

SEF983U

SEF976U

SEF977U

EC-140

< BASIC INSPECTION >

[VK56VD]

BASIC INSPECTION

2.

Rev engine between 2,000 and 3,000 rpm 2 or 3 times under no
load, then run engine at idle speed for approximately 1 minute.

3.

Check idle speed.
For procedure, refer to 

EC-530, "Inspection"

.

For specification, refer to 

EC-538, "Idle Speed"

.

Is the inspection result normal?

YES

>> GO TO 10.

NO

>> GO TO 4.

4.

PERFORM ACCELERATOR PEDAL RELEASED POSITION LEARNING

1.

Stop engine.

2.

Perform 

EC-146, "Work Procedure"

.

>> GO TO 5.

5.

PERFORM THROTTLE VALVE CLOSED POSITION LEARNING

Perform 

EC-147, "Work Procedure"

.

>> GO TO 6.

6.

PERFORM IDLE AIR VOLUME LEARNING

Perform 

EC-148, "Work Procedure"

.

Is Idle Air Volume Learning carried out successfully?

YES

>> GO TO 7.

NO

>> Follow the instruction of Idle Air Volume Learning. Then GO TO 4.

7.

CHECK IDLE SPEED AGAIN

1.

Start engine and warm it up to normal operating temperature.

2.

Check idle speed.
For procedure, refer to 

EC-530, "Inspection"

.

For specification, refer to 

EC-538, "Idle Speed"

.

Is the inspection result normal?

YES

>> GO TO 10.

NO

>> GO TO 8.

8.

DETECT MALFUNCTIONING PART

Check the Following.
• Check camshaft position sensor and circuit. Refer to 

EC-303, "DTC Logic"

.

• Check crankshaft position sensor and circuit. Refer to 

EC-299, "DTC Logic"

.

Is the inspection result normal?

YES

>> GO TO 9.

NO

>> Repair or replace malfunctioning part. Then GO TO 4.

9.

CHECK ECM FUNCTION

1.

Substitute with a non-malfunctioning ECM to check ECM function. (ECM may be the cause of the incident,
although this is rare.)

2.

Perform initialization of IVIS (NATS) system and registration of all IVIS (NATS) ignition key IDs. Refer to

SEC-51, "ECM : Work Procedure"

.

>> GO TO 4.

10.

CHECK IGNITION TIMING

1.

Run engine at idle.

2.

Check ignition timing with a timing light.
For procedure, refer to 

EC-531, "Inspection"

.

PBIA8513J

BASIC INSPECTION

EC-141

< BASIC INSPECTION >

[VK56VD]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

For specification, refer to 

EC-538, "Ignition Timing"

.

Is the inspection result normal?

YES

>> GO TO 19.

NO

>> GO TO 11.

11.

PERFORM ACCELERATOR PEDAL RELEASED POSITION LEARNING

1.

Stop engine.

2.

Perform 

EC-146, "Work Procedure"

.

>> GO TO 12.

12.

PERFORM THROTTLE VALVE CLOSED POSITION LEARNING

Perform 

EC-147, "Work Procedure"

.

>> GO TO 13.

13.

PERFORM IDLE AIR VOLUME LEARNING

Perform 

EC-148, "Work Procedure"

.

Is Idle Air Volume Learning carried out successfully?

YES

>> GO TO 14.

NO

>> Follow the instruction of Idle Air Volume Learning. Then GO TO 4.

14.

CHECK IDLE SPEED AGAIN

1.

Start engine and warm it up to normal operating temperature.

2.

Check idle speed.
For procedure, refer to 

EC-530, "Inspection"

.

For specification, refer to 

EC-538, "Idle Speed"

.

Is the inspection result normal?

YES

>> GO TO 15.

NO

>> GO TO 17.

15.

CHECK IGNITION TIMING AGAIN

1.

Run engine at idle.

2.

Check ignition timing with a timing light.
For procedure, refer to 

EC-531, "Inspection"

.

For specification, refer to 

EC-538, "Ignition Timing"

.

Is the inspection result normal?

YES

>> GO TO 19.

NO

>> GO TO 16.

16.

CHECK TIMING CHAIN INSTALLATION

Check timing chain installation. Refer to 

EM-62, "Removal and Installation"

.

Is the inspection result normal?

YES

>> GO TO 17.

NO

>> Repair the timing chain installation. Then GO TO 4.

17.

DETECT MALFUNCTIONING PART

Check the following.
• Check camshaft position sensor and circuit. Refer to 

EC-303, "DTC Logic"

.

• Check crankshaft position sensor and circuit. Refer to 

EC-299, "DTC Logic"

.

Is the inspection result normal?

YES

>> GO TO 18.

NO

>> Repair or replace malfunctioning part. Then GO TO 4.

18.

CHECK ECM FUNCTION 

1.

Substitute with a non-malfunctioning ECM to check ECM function. (ECM may be the cause of the incident,
although this is rare.)