Infiniti QX56 (Z62). Manual - part 550

EC-178

< DTC/CIRCUIT DIAGNOSIS >

[VK56VD]

P0011, P0021 IVT CONTROL

CAUTION:

Always drive at a safe speed.

3.

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

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000006217773

1.

CHECK OIL PRESSURE WARNING LAMP

1.

Start engine.

2.

Check that oil pressure warning lamp is not illuminated.

Is oil pressure warning lamp illuminated?

YES

>> Go to 

LU-7, "Inspection"

.

NO

>> GO TO 2.

2.

CHECK INTAKE VALVE TIMING CONTROL SOLENOID VALVE

Refer to 

EC-179, "Component Inspection (Intake Valve Timing Control Solenoid Valve)"

.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> Replace malfunctioning intake valve timing control solenoid valve. Refer to 

EM-61, "Exploded

View"

.

3.

CHECK CRANKSHAFT POSITION SENSOR

Refer to 

EC-301, "Component Inspection (Crankshaft Position Sensor)"

.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Replace crankshaft position sensor. Refer to 

EM-106, "Exploded View"

.

4.

CHECK CAMSHAFT POSITION SENSOR

Refer to 

EC-306, "Component Inspection (Camshaft Position Sensor)"

.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Replace malfunctioning camshaft position sensor. Refer to 

EM-106, "Exploded View"

.

5.

CHECK CAMSHAFT (INTAKE)

Check the following.

Selector lever

1st or 2nd position

Driving location uphill

Driving vehicle uphill
(Increased engine load will help maintain the driving 
conditions required for this test.)

PBIA8559J

P0011, P0021 IVT CONTROL

EC-179

< DTC/CIRCUIT DIAGNOSIS >

[VK56VD]

C

D

E

F

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EC

N

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• Accumulation of debris on the signal plate of camshaft front end
• Chipping signal plate of camshaft front end
Is the inspection result normal?

YES

>> GO TO 6.

NO

>> Remove debris and clean the signal plate of camshaft

front end or replace camshaft. Refer to 

EM-61,

"Exploded View"

 or 

EM-75, "Removal and Installation"

.

6.

CHECK TIMING CHAIN INSTALLATION

Check service records for any recent repairs that may cause timing chain misalignment.

Are there any service records that may cause timing chain misalignment?

YES

>> Check timing chain installation. Refer to 

EM-75, "Removal and Installation"

.

NO

>> GO TO 7.

7.

CHECK LUBRICATION CIRCUIT

Perform “Inspection of Camshaft Sprocket (INT) Oil Groove”. Refer to 

EM-77, "Inspection"

.

Is the inspection result normal?

YES

>> GO TO 8.

NO

>> Clean lubrication line.

8.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-40, "Intermittent Incident"

.

>> INSPECTION END

Component Inspection (Intake Valve Timing Control Solenoid Valve)

INFOID:0000000006217774

1.

CHECK INTAKE VALVE TIMING CONTROL SOLENOID VALVE-I

1.

Turn ignition switch OFF.

2.

Disconnect intake valve timing control solenoid valve harness connector.

3.

Check resistance between intake valve timing control solenoid valve terminals as per the following.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Replace malfunctioning intake valve timing control solenoid valve. Refer to 

EM-61, "Exploded

View"

.

2.

CHECK INTAKE VALVE TIMING CONTROL SOLENOID VALVE-II

1.

Remove intake valve timing control solenoid valve.

JMBIA0962ZZ

Terminals

Resistance

1 and 2

7.0 - 7.7 

Ω

 [at 20

°

C (68

°

F)]

1 or 2 and ground

∞

 

Ω

(Continuity should not exist)

EC-180

< DTC/CIRCUIT DIAGNOSIS >

[VK56VD]

P0011, P0021 IVT CONTROL

2.

Provide 12 V DC between intake valve timing control solenoid
valve terminals 1 and 2, and then interrupt it. Check that the
plunger moves as shown in the figure.

CAUTION:

Never apply 12 V DC continuously for 5 seconds or more.
Doing so may result in damage to the coil in intake valve
timing control solenoid valve.
NOTE:
Always replace O-ring when intake valve timing control
solenoid valve is removed.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Replace malfunctioning intake valve timing control solenoid valve. Refer to 

EM-61, "Exploded

View"

.

JMBIA0079ZZ

P0031, P0032, P0051, P0052 A/F SENSOR 1 HEATER

EC-181

< DTC/CIRCUIT DIAGNOSIS >

[VK56VD]

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P0031, P0032, P0051, P0052 A/F SENSOR 1 HEATER

DTC Logic

INFOID:0000000006217775

DTC DETECTION 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

1.

Start engine and let it idle for at least 10 seconds.

2.

Check 1st trip DTC.

Is 1st trip DTC detected?

YES

>> Go to 

EC-181, "Diagnosis Procedure"

.

NG

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000006217776

1.

CHECK AIR FUEL RATIO (A/F) SENSOR 1 POWER SUPPLY CIRCUIT

1.

Disconnect air fuel ratio (A/F) sensor 1 harness connector.

2.

Turn ignition switch ON.

3.

Check the voltage between A/F sensor 1 harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> GO TO 2.

 DTC No.

Trouble diagnosis

(Trouble diagnosis content)

DTC detecting condition

Possible cause

P0031

A/F SEN1 HTR (B1)
[A/F sensor 1 heater (bank 
1) control circuit low]

The current amperage in the A/F sensor 1 heater 
circuit is out of the normal range.
(An excessively low voltage signal is sent to ECM 
through the A/F sensor 1 heater.)

• Harness or connectors

(The A/F sensor 1 heater circuit is 
open or shorted.)

• A/F sensor 1 heater

P0032

A/F SEN1 HTR (B1)
[A/F sensor 1 heater (bank 
1) control circuit high]

The current amperage in the A/F sensor 1 heater 
circuit is out of the normal range.
(An excessively high voltage signal is sent to ECM 
through the A/F sensor 1 heater.)

• Harness or connectors

(The A/F sensor 1 heater circuit is 
shorted.)

• A/F sensor 1 heater

P0051

A/F SEN1 HTR (B2)
[A/F sensor 1 heater (bank 
2) control circuit low]

The current amperage in the A/F sensor 1 heater 
circuit is out of the normal range.
(An excessively low voltage signal is sent to ECM 
through the A/F sensor 1 heater.)

• Harness or connectors

(The A/F sensor 1 heater circuit is 
open or shorted.)

• A/F sensor 1 heater

P0052

A/F SEN1 HTR (B2)
[A/F sensor 1 heater (bank 
2) control circuit high]

The current amperage in the A/F sensor 1 heater 
circuit is out of the normal range.
(An excessively high voltage signal is sent to ECM 
through the A/F sensor 1 heater.)

• Harness or connectors

(The A/F sensor 1 heater circuit is 
shorted.)

• A/F sensor 1 heater

DTC

A/F sensor 1

Ground

Voltage

Bank

Connector

Terminal

P0031, P0032

1

F67

5

Ground

Battery voltage

P0051, P0052

2

F68

5